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Volume 40, Issue 4
Displaying 1-50 of 60 articles from this issue
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Atsutoshi OTA, Hiroshi SUHARA, Yoichi KAWASHIMA1992 Volume 40 Issue 4 Pages 833-836
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChiroptical properties of (R)-(+)- and (S)-(-)-2-(2-hydroxy-5-methoxyphenyl)-4-methyl-2H-1, 4-benzothiazin-3(4H)-one ((R)- and (S)-2), and (S)-(-)-4-methyl-2-phenyl-2H-1, 4-benzothiazin-3(4H)-one ((S)-3), related compounds with a novel Ca2+ antagonist, Semotiadil ((R)-1; SD-3211), were reported. The absorption band of each chromophore was assigned by reference to the ultraviolet (UV) spectra of 2-unsubstituted benzothiazine (4) and thiazine (5); in the circular dichroism (CD) spectra of (R)-2, (S)-2 and (S)-3, their maximum wave lengths corresponded approximately to those of the UV absorptions of each chromophore. The CD spectra suggested that the conformation of (S)-3 was similar to that of (R)-2 and (S)-2, in contrast to the X-ray crystallographic result previously analyzed. The solution conformations of these compounds were discussed by reference to the helicity rule.View full abstractDownload PDF (673K) -
Saburo SHIMABAYASI, Yukihiro IKEDA, Miwako KITAMURA, Chikako HARADA1992 Volume 40 Issue 4 Pages 837-842
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMequitazine (Meq; 10-(3-quinuclidinylmethyl)phenothiazine) disolved in water formed a complex with polyvinylpyrrolidone (PVP) due to hydrophobic interaction and with sodium alginate (NaAlg) by virtue of ion-dipole and/or -ion interaction between carboxylate groups and quinuclidinyl groups. The binding ratio of Meq to NaAlg was higher than that to PVP, while the adsorption amount of PVP by solid Meq was higher than that of NaAlg. It was shown by electrophoresis that a positive charge of Meq particles was reversed to a negative one after the adsorption of alginate. The degree of crystallinity of Meq recrystallized from an aqueous solution of these polymers was examined by an X-ray powder diffractometry. It decreased with polymer concentration owing to the complex formation and adsorption onto its crystal nuclei and/or embryos.View full abstractDownload PDF (947K) -
Norimitsu HAMAMICHI, Tadashi MIYASAKA1992 Volume 40 Issue 4 Pages 843-845
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSα-(Aminomethylene)-β-D-ribofuranosylpurine-6-acetamide (4) and the ethyl acetate (9) have been synthesized by catalytic hydrogenation of 6-cyanomethylenepurine derivatives (3 and 7). 6-Cyanomethylenepurines were obtained by substitution of 6-chloro-9-(2, 3-O-isopropylidene-β-D-ribofuranosyl)purine (1) with α-cyanoacetamide and ethyl cyanoacetate, followed by deprotection of the isopropylidene group. Substitution on 4 and 9 with benzylamine and aniline gave the corresponding N-benzyl- and N-phenyl-substituted α-(aminomethylene)-β-D-ribofuranosylpurine-6-acetamides (5) and the ethyl acetate (10), respectively.View full abstractDownload PDF (636K) -
Ichiro ISHIKAWA, Victor E. KHACHATRIAN, Raphael G. MELIK-OHANJANIAN, N ...1992 Volume 40 Issue 4 Pages 846-850
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS7-Alkyl-1, 3, 6-trimethylpyrrolo[2, 3-d]pyrimidine-2, 4(1H, 3H)-diones were readily synthesized by treatment of 6-alkylamino-5-allyl-1, 3-dimethyluracils, which were derived from 5-allyl-6-chloro-1, 3-dimethyluracil and alkylamines, with bis(acetonitrile) palladium (II) chloride. In addition, 4-alkylamino-2, 5-dimethyl-2, 3-dihydrofuro[3, 2-e]pyrimidin-6-ones were easily synthesized by treatment of 5-allyl-6-chloro-1-methyluracil with alkylamines.View full abstractDownload PDF (865K) -
Nobuko SAKURAI, Masato KOBAYASHI, Atsushi SHIGIHARA, Takao INOUE1992 Volume 40 Issue 4 Pages 851-853
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new phenol glycoside named berchemolide was isolated together with (+)-catechin and (-)-epicatechin (as acetates), from the stems of Berchemia racemosa SIEB. et ZUCC. (Rhamnaceae). The structure of berchemolide, having a dimeric dilactone structure with a 22-membered ring, was determined on the basis of spectral and chemical investigations. The conformation of berchemolide was calculated by MNDO (modified neglect of diatomic overlap).View full abstractDownload PDF (550K) -
Sigeru OHMIYA, Masayo NOGUCHI, Shinji INA, Hajime KUBO, Hirotaka OTOMA ...1992 Volume 40 Issue 4 Pages 854-857
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhotoaddition reactions of pyrroles (2-4) and indoles (5-8) to N-methyl-2-pyridone (1) have been investigated. The reaction occurred primarily by way of addition of the C2-H bond of the pyrrole ring and the C3-H bond of the indole ring to the pyridone nucleus, yielding 4-substituted 3, 4-dihydro-1-methylpyridin-2(1H)-ones (9 from pyrrole; 13 and 17 from indoles) and 6-substituted 3, 6-dihydro-1-methylpyridin-2(1H)-ones (10 from pyrrole; 14 and 18 from indoles). The presence of a methyl group(s) at the reactive site(s) of pyrrole and indole resulted in the formation of the products arising from the addition of the C3-H bond of the pyrrole ring, and the N1-H, C2-H and C6-H bonds of the indole ring. N-Methylpyrrole (4) and N-methylindole (8) did not give any detectable amount of the addition product.View full abstractDownload PDF (693K) -
Hajime NITTA, Koichi TAKIMOTO, Ikuo UEDA1992 Volume 40 Issue 4 Pages 858-863
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReaction of benzaldehyde (1a) with methyl acetoacetate (2) in the presence of morpholine (or piperidine) and AcOH in refluxing C6H6 yielded a new condensation product, 1, 5-dimethoxycarbonyl-2-methyl-4-morpholino (or piperidino)-6-phenyl-1, 3-cyclohexadiene (3a or 10a), along with a usual product, benzylideneacetoacetate (4a). Under the conditions determined as optimum, 3a was prepared in 86% yield. However, reaction of 1a and 2 in the presence of morpholine (or piperidine) in EtOH solution yielded 4a, a poly-substituted cyclohexanone derivative (5a) and a cyclohexenone derivative (7a), while the production of 3a was not detected. Compound 3a (or 10a) was also prepared by an alternative procedure of condensation of 5a or 6a with morpholine (or piperidine) in the presence of TiCl4. Compound 6a was prepared by dehydration of 5a under acidic conditions. Acid hydrolysis of 3a afforded 6'a, which is the C-4 epimer of 6a. The configurations of 3a, 6a and 6'a were assigned on the basis of the proton nuclear magnetic resonance (1H-NMR) spectra. Mechanisms of the formation of 3a are discussed. Some of 3 and related compounds exhibited potent calcium channel-blocking activity.View full abstractDownload PDF (862K) -
Hitoshi ISHIDA, Shunya KINOSHITA, Ryukan NATSUYAMA, Haruo NUKAYA, Kuni ...1992 Volume 40 Issue 4 Pages 864-868
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo sodium scymnol sulfates, 1 and 2, were isolated by two steps of chromatography from the bile of Lamna ditropis. Compound 2 was identified as (24R, 25S)-(+)-3α, 7α, 12α, 24, 26-pentahydroxy-5β-cholestan-27-yl sodium sulfate and the structure of 1 was determined to be (24R, 25R)-(+)-3α, 7α, 12α, 24, 26-pentahydroxy-5β-cholestan-27-yl sodium sulfate, based on the spectral data and chemical transformations. Based on the physical data, the structures of two new anhydroscymnols, 3 and 4, prepared from 1 by alkaline degradation with aqueous potassium hydroxide, were established as (24R, 25R)-(+)-24, 26-epoxy-5β-cholestane-3α, 7α, 12α, 27-tetrol and (24R)-(+)-26, 27-epoxy-5β-cholestane-3α, 7α, 12α, 24-tetrol, respectively. The other shark bile constituents were also analyzed, and the hydrolysis of the sulfate ester function of 1 and 2 was examined.View full abstractDownload PDF (1485K) -
Haruhiro FUJIMOTO, Yasuhiro TAKANO, Mikio YAMAZAKI1992 Volume 40 Issue 4 Pages 869-872
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree metabolites, tentatively named HS-A, -B and -C, were isolated from a mushroom, Hebeloma spoliatum, as the fatal toxic principles to mice. HS-A was indentified as 3-acetyl-2(3'-hydroxy-3'-methyl)glutarylcrustulinol, which has been isolated from Hebeloma crustuliniforme and H. sinapizans as a cytotoxic principle. HS-B and -C were deduced to be 3, 21-diacetyl-2-(3'-hydroxy-3'-methyl)glutarylcrustulinol and 3-acetyl-2-(3'-hydroxy-3'-methyl)glutarylanhydrocrustulinol, respectively, from their chemical and spectral data.Intraperitoneal administration of HS-A, -B and -C at a dose of 100 mg/kg caused death after paralysis of the limbs in mice. The compounds caused relaxation of mouse small intestine contracted by acetylcholine chloride or barium chloride treatment in vitro. They appear to exhibit a paraverine-like relaxation effect.View full abstractDownload PDF (738K) -
Takehiro SANO, Jun TODA, Takeshi OHSHIMA, Yoshisuke TSUDA1992 Volume 40 Issue 4 Pages 873-878
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel synthetic route to Erythrina alkaloids consisting in [2+2] intermolecular photocycloaddition of the isoquinolinodioxopyrroline 4 to 2-trimethylsilyloxybutadienes and the subsequent ring enlargement reaction of the trimethylsilyloxyvinylcyclobutane 5 by thermal or tetrabutylammonium flouride(TBAF)-induced 1, 3-shift was developed. The TBAF method was particularly useful, offering a good yield under mild reaction conditions. Thus, photoannulation of 4 with 1-methoxy-3-trimethylsilyloxybutadiene, followed by hydride reduction, TBAF-induced 1, 3-shift, and hydrogenation gave the 7α-hydroxy-2, 8-dioxoerythrinan 19 in overall 45% yield, and this product was converted, in 70% yield, into the 1, 7-cycloerythrinan 24, a key intermediate for the total synthesis of Erythrina alkaloids.View full abstractDownload PDF (912K) -
Mitsunobu NAKAMURA, Hiroaki TAKAYANAGI, Kimio FURUHATA, Haruo OGURA1992 Volume 40 Issue 4 Pages 879-885
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe products of Fischer's methyl glycosylation of 3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (KDN) revealed existence of an the anomeric equilibrium between α, β-furanose and α, β-pyranose of KDN. In spite of the anomeric equilibrium, peracetylation of KDN and its derivatives by acetic anhydride with pyridine gave only α- and β-pyranose derivatives. The obtained methyl glycosides and hexa-O-acetyl derivatives were characterized by X-ray, nuclear magnetic resonance and cicular dichroism spectral analyses.View full abstractDownload PDF (1037K) -
Tsuneatu NAGAO, Hikaru OKABE1992 Volume 40 Issue 4 Pages 886-888
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new oleanolic acid 3, 28-O-bisdesmosides, scaberosides B7, B8 and B9, were isolated as minor saponins from the root of Aster scaber THUNB. (Compositae), and their structures were determined based on spectral and chemical evidence as follows. Scaberoside B7 is 3-O-β-D-glucopyranosyluronic acid oleanolic acid 28-{O-β-D-apiofuranosyl-(1→3)-[O-β-D-xylopyranosyl-(1→4)]-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl} ester, scaberoside B8, 3-O-β-D-glucopyranosyl oleanolic acid 28-[O-β-D-xylopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] ester, and scaberoside B9, 3-O-β-D-glucopyranosyluronic acid oleanolic acid 28-{O-α-L-rhamnopyranosyl-(1→2)-[O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranosyl} ester. Scaberosides B7 and B9 were obtained as their methyl esters.View full abstractDownload PDF (564K) -
Cheng-Bin CUI, Yasuhiro TEZUKA, Tohru KIKUCHI, Hirofumi NAKANO, Tatsuy ...1992 Volume 40 Issue 4 Pages 889-898
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSProcyanidin B-5 (1), epicatechin-(4β→8)-epicatechin-(4β→6)-epicatechin (2), and epicatechin-(4β→6)-epicatechin-(4β→8)-epicatechin-(4β→6)-epicatechin (3), which showed an inhibitory effect toward protein kinase C, were isolated from the rhizomes of Davallia mariesii MOORE. Detailed analyses of their 1H- and 13C-nuclear magnetic resonance spectra were carried out by the use of two-dimensional nuclear magnetic resonance techniques.View full abstractDownload PDF (1134K) -
Kazuhiko TAKE, Kazuo OKUMURA, Koichi TAKIMOTO, Minoru OHTSUKA, Youichi ...1992 Volume 40 Issue 4 Pages 899-906
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 1, 1'-biphenyl-2, 6-dicarboxylic acid diesters with an aminoalkyl group in the ester function were synthesized and examined for their inhibitory activity on detrusor contraction in vitro and in vivo. In the in vivo test, arrhythmia was observed as a side effect. Among those compouds synthesized, 2-methyl 6-[4-(1-methylpiperidinyl)]3-hydroxy-5-methyl-2'-nitro-1, 1'-biphenyl-2, 6-dicarboxylate (18) showed strong inhibitory activity on detrusor contractions in vivo (ED50=0.54 mg/kg i.v., ED50=7.2 mg/kg i.d.) and good separation from the side effect. Compound 18 was chosen for further pharmacological evaluation as an agent for the treatment of overactive detrusor.View full abstractDownload PDF (916K) -
Yoshitaka OHISHI, Teruo MUKAI, Michiko NAGAHARA, Motoyuki YAJIMA, Nori ...1992 Volume 40 Issue 4 Pages 907-911
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS5-Alkyl-3-carboxymethylrhodanines (2) were prepared from 5-alkylmethylidene-3-carboxymethylrhodanines (1). The exo double bond of 1 was successfully reduced with NaBH4. The 1, 4-addition reaction path was confirmed on the basis of proton nuclear magnetic resonance spectrum of the product (4b) obtained from the reduction of 3 using NaBD4. Optical resolution of the tert-butyl compound (2i) was achieved upon epimerization-crystallization method using L-3-amino-ε-caprolactam. The alkyl compounds (2) and the optical active compounds ((+)-2i, (-)-2i) were evaluated for aldose reductase inhibitory potency.View full abstractDownload PDF (838K) -
Yoshinari SATOH, Masaharu ICHIHASHI, Kazuo OKUMURA1992 Volume 40 Issue 4 Pages 912-919
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe synthesis of new 2-hydroxymethyl- and 2-cyano-1, 4-dihydropyridines possessing a heteroatom-substituted alkyl ester group at the 5-position of the nucleus in described. The esters were introduced via a suitable method selected from the modified Hantzsch method (method A), the hydrolysis of a chloroethyl ester obtained by method A (method B) or the replacement of the chlorine atom with various kinds of amino groups (method C). Hydroxymethyl and cyano groups at the 2-position were prepared in a similar manner to that described in a previous papare.1)The hypotensive activities of the compounds prepared in this paper were compared with the corresponding alkyl ester at the 5-position reported previously. It was found that N-benzylmethylaminoethyl esters, especially N-(4-chlorobenzyl)-and N-(3, 4-dichlorobenzyl)-N-methylaminoethyl esters, were suitable substituents at the 5-position of the 1, 4-dihydropyridine nucleus and that these substituents were somewhat more effective for hypotensive activity than simple alkyl esters in a series of 2-hydroxymethyl-1, 4-dihydropyridine derivatives. But it was found that the effect was reversed in a series of 2-cyano-1, 4-dihydropyridine derivatives. Both of them were found to be inferior to nilvadipine (1c), accepted in clinical use for the treatment of hypertension.View full abstractDownload PDF (1068K) -
Yukio KITADE, Akiyuki SUZUKI, Kosaku HIROTA, Yoshifumi MAKI, Hideo NAK ...1992 Volume 40 Issue 4 Pages 920-924
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSVarious 3-substituted 3'-azido-3'-deoxythymidine analogs (2a-i) were prepared by the reaction of 3'-azido-3'-deoxythymidine (1), AZT with N, N-dimethylformamide dialkylacetal or alkyl bromide in the presence of base and their activities against human-immunodeficiency virus type-1 (HIV-1) were evaluated. The corresponding 5'-triphosphate analogs (9) were also synthesized in order to examine inhibition of HIV-1 reverse transcriptase activity. Beyond expectation, some N3-derivatives of AZT were found to reserve the anti-HIV-1 activity to some extent. Among the compounds (2a-i) obtained, 3-allyl-AZT (2e) was the most active against HIV-1 replication in MT-4 cells in vitro with an EC50 value of 0.9μM. 3-Allyl-AZT 5'-triphosphate (9e), however, exhibited no inhibition of HIV-1 reverse transcriptase activity.View full abstractDownload PDF (964K) -
Chisako YAMAGAMI, Narao TAKAO1992 Volume 40 Issue 4 Pages 925-929
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe log k' (k' : capacity factor) values of various heteroaromatic compounds were measured by reversed-phase high performance liquid chromatography (RPLC) using a Capcell pack C18 column and methanol-water eluents, and the relationship with the log P values (P : 1-octanol-water partition coefficient) was examined as a function of the mobile phase composition. Furans having nonhydrogen-bonding or weakly hydrogen-accepting substituents exhibited a good linear relationship at 50% MeOH concentration. Amphiprotic sibstituents, CONHR, showed an acceleration effect (less retained than nonhydrogen-bonders and hydrogen-acceptors under the condition of equivalent log P), as is often observed in heterocyclic systems. The relationship was more complicated at other methanol contents, due to different retention behavior demonstrated by the ester-type substituents, CO2R and CONR2 (ester effect), To gain more insight into this ester effect, the retention behavior of ester derivatives of various heteroaromatics such as furan, benzofuran, N-Me pyrrole and indole was also studied. The factors affecting the log P-log k' relationship were discussed, and the optimum RPLC condition for predicting the log P value was described.View full abstractDownload PDF (787K) -
Ikuo MORIGUCHI, Shuichi HIRONO, Yasuo MATSUSHITA, Qian LIU, Izumi NAKA ...1992 Volume 40 Issue 4 Pages 930-934
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA 1991 version of fuzzy adaptive least squares (FALS91) has been developed to analyze structure-activity rating data for generation of QSAR (quantitative structure-activity relationship) models. Improvements were made in this version especially to the error-correcting feedback adaptation of discriminant functions to avoid falling into a local optimum. This paper showed effective applications of FALS91 to structure-activity correlation of 29 antihypertensive arylacryloylpiperazine derivatives and structure-toxicity correlation of human acute toxicity of 504 organic chemicals as typical examples of small- and large-scale data sets, respectively. These examples demonstrated the high reliability of FALS91 in both recognition and leave-one-out prediction.View full abstractDownload PDF (698K) -
Kenyu SHIBATA, Shigehiro TAKEGAWA, Naoyuki KOIZUMI, Nobuaki YAMAKOSHI, ...1992 Volume 40 Issue 4 Pages 935-941
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2-Azachlormadinone acetate (5a, 17-acetoxy-6-chloro-2-azapregna-4, 6-diene-3, 20-dione), 2-oxachlormadinone acetate (6, 17-acetoxy-6-chloro-2-oxapregna-4, 6-diene-3, 20-dione) and the derivatives were prepared as potential antiandrogenic agents. Biological evaluation showed that 5a and 6 had a potent antiandrogenic activity when tested in the castrated male rat.View full abstractDownload PDF (1129K) -
Toshimitsu HAYASHI, Toshiyuki KAJI, Masami TAKEBAYASHI, Rie SOEJIMA, N ...1992 Volume 40 Issue 4 Pages 942-945
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSBioassay-guided fractionation of Gardeniae Fructus extract (GFE), which stimulates the proliferation of cultured endothelial cells, led to the isolation of glycerol and D-mannitol. Both compounds significantly increased the incorporation of [3H]thymidine and [14C]leucine into the acid-insoluble fraction of bovine aortic endothelial cell layers in culture. This clearly indicated that glycerol and D-mannitol are active components of GFE on endothelial cell proliferation. On the other hand, they did not change the number of cultured vascular smooth muscle cells from bovine aorta. Glycerol and D-mannitol may be benefical drugs for vascular disorders.View full abstractDownload PDF (654K) -
Yoshinori INOSE, Toshio MIYASE, Akira UENO1992 Volume 40 Issue 4 Pages 946-953
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAfter further investigation of more polar fractions of Solidago virga-aurea L. (Compositae), 11 new oleanane-type saponins named solidagosaponins X-XX (1-11) were isolated, together with two known saponins, virgaureasaponin 1 (12) and bellissaponon BA2 (13). These new saponins contain various acyl groups, and four of them were tridesmosidic glycoside. Their structures were established on the basis of spectroscopic and chemical evidence.View full abstractDownload PDF (1008K) -
Yukihiro OZAKI1992 Volume 40 Issue 4 Pages 954-956
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTetramethylpyrazine (TMP) is one of the alkaloids contained in Ligusticum wallichii FRANCH (L.wallichii). Ferulic acid (FA) is a phenolic compound contained in L. wallichii and Angelica sinensis (OLIV.) DIELS (A. sinesis). The present study was carried out to examine the antiinflammatory effect and to elucidate the mode of the effect of TMP and FA. Both compounds significantly inhibited the edema induced by carrageenin, the increase of the dye leakage induced by acetic acid and the granuloma formation induced by cotton pellet. And also, TMP and FA inhibited the number of writhes induced by acetic acid. From these results, it is suggested that both compounds have the antiinflammatory effect and the analgesic effect, and both compounds exert an antiinflammatory effect at the early and the late stages of processes in the inflammatory pathology.View full abstractDownload PDF (560K) -
Masahiko NANAMI, Kiyoshi ZAITSU, Yosuke OHKURA1992 Volume 40 Issue 4 Pages 957-960
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA method for the preparation of insulin derivatives having pretected sulfhydryl group(s) on definite site(s) on the molecule which uses anion-exchange high performance liquid chromatography on a TSKgel DEAE-2SW column for separation is described. Porcine insulin reacts with N-succinimidyl S-acetylthioacetate to afford four species of insulin derivatives that have S-acetylthioglycoloyl group(s) at i) Gly(A1), ii) Gly(A1) and Phe(B1), iii) Gly(A1) and Lys(B29), and iv) Gly(A1), Phe(B1) and Lys(B29) positions. An insulin derivative which has a group at the Lys(B29)-position is prepared by the S-acetylthioglycoloylation of Gly(A1), Phe(B1)-dicitraconyl insulin followed by decitraconylation. The five derivatives are readily deacetylated with hydroxylamine to yield the corresponding sulfhydryl insulin derivatives.View full abstractDownload PDF (618K) -
Ikuo KASHIWAKURA, Miho MURAKAMI, Yukitoshi HAYASE, Yoshinari TAKAGI1992 Volume 40 Issue 4 Pages 961-964
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe have purified a factor, hematopoietic promoting factor (HPF), from porcine kidney extract (PKE), which exhibits a promoting activity on granulocyte/macrophage (GM) colony and burst-forming-unit-erythroid (BFU-E)-derived colony formation by progenitors from murine bone marrow cells in vitro. The addition of HPF resulted in an enhancement of the GM colonies as well as BFU-E-derived colonies, but did not enhance the colony-forming-unit-erythroid (CFU-E)-derived colony formation. HPF was added to the BFU-E cultures together with cytokines, such as recombinant murine interleukin-3 (IL-3), recombinant murine GM colony-stimulating-factor (GM-CSF) and recombinant human G-CSF, which have all been shown to enhance BFU-E growth. The combination of HPF plus these cytokines resulted in an enhancement of benzidine negative colony formation in comparison to the case of each cytokine alone; however, no increase was found on BFU-E colony formation.HPF is able to enhance the granulopoiesis and erythropoiesis in vitro. And the synergistic activity of HPF is significantly affected by the presence of cytokines in the cultures.View full abstractDownload PDF (726K) -
Hironobu KOGA, Nobuko MORI, Hidenori YAMADA, Yukio NISHIMURA, Kazuo TO ...1992 Volume 40 Issue 4 Pages 965-970
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSEmploying soluble denatured protein substrates and their derivatives, the proteolytic activity of rat cathepsin H was investigated. The enzyme showed aminopeptidase activity which sequentially released amino acid from the N-terminal of the substate. The aminopeptidase activity did not act on Nα-acetylated peptides and showed moderate ionic-strength dependence when methionyl-methylcoumarylamide was employed as a substrate. These results indicate that the activity essentially requires an N-terminal free amino group of the substrate and recognizes it electrostatically to some extent. On the other hand, the enzyme was also indicated to exhibit endopeptidase activity by employing appropriate Nα-acetylated peptide substrates. In contrast to the aminopeptidase activity, the endopeptidase activity showed rather strict specificity, preferring hydrophobic residues at P2 and P3 sites. Because of the broad specificity and high efficiency of the aminopeptidase activity, it was difficult to directly observe endopeptidase activity in the digestion of large peptide substrates with a free α-amino terminal. Thus, this is the first experimental evidence that indicates endopeptidase activity by assigning internal peptide bonds cleaved by this activity. From this data, we proposed a model of the binding site of this enzyme.View full abstractDownload PDF (922K) -
Mitsuo TANAKA, Toshihiro IIO, Toshikazu TABATA1992 Volume 40 Issue 4 Pages 971-975
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSLysosomal acid cholesteryl eater hydrolase (acid CEH, EC. 1.1.1.13) activity was inhibited by addition of an increasing amount of d=1.21 bottom fraction from rat serum (Lipids in press). To clarify the mechanism of this inhibition, rat native and modified albumin were added to the assay mixture and thier effects on acid CEH activity were examined. The inhibitory effect on acid CEH activity was dependent on the concentration of rat albumin. Albumin of various mammalian species, including human, boving and rabbir, also inhibited acid CEH activity. This inhibitory activity was markedly increased by heat treatment, the effect increasing in parallel with the prolongation of the treatment. Moreover, this albumin-dependent inhibition of acid CEH activity was also markedly increased by methylation of albumin. In contrast, the inhibition of acid CEH activity by modified albumins, such as acetyl albumin, succinyl albumin and glycine methyl eater albumin, was much lower than that of albumin, and no stimulatory effect of heat treatment on the albumins was observed. The heat-treated albumin-dependent inhibition of acid CEH activity was not abolished in the presence of sodium dexzycholate. The values of Vmax obtained were similar with or without heat-treated albumin.these results suggest that the inhibitory effects of heat-treated albumin may be due to an intrinsic and characteristic property of the lipid/water interface, and that the stimulatory effect of heat treatment on albumin-dependent inhibition may be due to heat-induced changes in the affinity and conformation of albumin.View full abstractDownload PDF (741K) -
Kazumichi SASAOKI, Takashi HIROSHIMA, Shunji KUSUMOTO, Kiyoshi NISHI1992 Volume 40 Issue 4 Pages 976-980
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReversed-phase high-performance liquid chromatography (RP-HPLC) and protein-chemical analysis revealed that only Asn88 in recombinant human interleukin 2 (rIL-2) is liable to be deamidated during a long period of storage in aqueous solutions (pH 5.0) at 25°C, even though there are eight asparagine and six glutamine residues. The deamidation occurred more easily at 40°C than at 25°C but did not occur at all at tempratures below 5°C. The biological activity of Asn88-deamidated rIL-2 was found to be almost the same as that of intact rIL-2, whereas its isoelectric point (pI 7.6) is different from that of intact rIL-2 (pI 7.9).View full abstractDownload PDF (866K) -
Takashi AOKI, Tomoko TAKASAKI, Hiroshi MIURA, Hiroyuki WATABE1992 Volume 40 Issue 4 Pages 981-985
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe concentration of laminin including laminin variants in serum samples was measured by a double-antibody radioimmunoassay using intact laminin. The mean level in 92 normal subjects (47 men and 45 women) was defined as 1 unit (U)/ml, and the cut-off value (2 S.D. above the mean) was 1.37 U/ml. Mean laminin level in 391 patients with various malignancies was 1.50±0.86 U/ml. Laminin levels were elevated in various cancer patients, and in 45.0% (176/391) the values exceeded the cut-off level; in patients with cancer of the stomach or pancreas, positivity rate exceeded 60%. Mean laminin concentration for 130 pregnant women (2.06±U/ml) was also significantly higher than that of normal controls, but concentrations for patients with various benign diseases were within a low range (0.55±0.29-1.10±0.29 U/ml). In the stomach or pancreas cancer patients, a positive correlation between laminin level and tumor progression or course of the disease was observed. These findings indicate that serum laminin level is potentially useful in the diagnosis and monitoring of certain cancers.View full abstractDownload PDF (751K) -
Katsuyuki NAGAI, Jiro TANAKA, Tadashi KIHO, Shigeo UKAI1992 Volume 40 Issue 4 Pages 986-989
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe conjugate of mitomycin C (MMC) with linear (1→3)-β-D-glucan from Alcaligenes faecalis var. myxogenes IFO 13140 was synthesized and its antitumor activities investigated. The conjugate (MMC-carboxymethylated linear (1→3)-β-D-glucan (CMPS)) was obtained by treatment of CMPS with MMC in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide. In vitro cytotoxicity of MMC-CMPS against L1210 leukemia cells was similar to that of MMC. In i.p.-i.p. system in vivo against P388 leukemia in mice, the maximum increase of MMC-CMPS conjugate in life span (ILSmax) was higher than that of MMC but the therapeutic index was reduced. However, the antitumor activity of MMC-CMPS conjugate against subcutaneously implanted sarcoma 180 solid tumor in mice by i.p. administration was similar to that of MMC at a dose of 1.5 mg eq MMC/kg/d×7 and the reduction of the number of leukocytes caused by MMC was suppressed by attaching MMC to CMPS. In addition, on assay using serum of sarcoma 180 solid tumor-bearing mice with injection of MMC-CMPS conjugate, a drastic loss of tumor cells and an increase in polymorphonuclear leukocytes (PMN) were observed. This result suggested that MMC-CMPS conjugate induced tumor-regressing factor similar to CMPS.View full abstractDownload PDF (713K) -
Ryoko GONDA, Masashi TOMODA, Katsutoshi TAKADA, Naoko OHARA, Noriko SH ...1992 Volume 40 Issue 4 Pages 990-993
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe controlled Smith degradation of ukonan A, a phagocytosis-activating polysaccharide isolated from the rhizome of Curcuma longa L., was performed. The reticuloendothelial system-potentiating, anti-complementary and alkaline phosphatase-inducing activities of ukonan A and its degradation products were investigated. Methylation analyses of both the primary and the secondary Smith degradation products indicated that the core structural features of ukonan A include a backbone chain mainly composed of β-1, 3-linked D-galactose, β-1, 4-linked D-xylose and α-1, 2-linked L-rhamnose residues. All of the galactose units in the backbone carry side chains composed of α-L-arabino-β-D-galactosyl or β-D-galactosyl residues at position 6.Ukonan A has a remarkabke effect on each of the three kinds of immunological activities. Periodate oxidation caused pronounced decrease or disappearance of the activities, but the controlled Smith degradation product having the core structure of polysaccharide showed considerable restoration of these activities.View full abstractDownload PDF (682K) -
Hiroyuki INAGAWA, Takashi NISHIZAWA, Daisuke TSUKIOKA, Takuya SUDA, Yu ...1992 Volume 40 Issue 4 Pages 994-997
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn order to seek a macrophage-antivating substance, lipopolysaccharide (LPS) of plant origin other than that of wheat flour was surveyed. A large amount of LPS (10-100 μg/g) was detected in Laminaria japonica (kelp, ?? ?? ), Curcuma longa (turmeric, ?? ?? ), Underia pinnatifida ( ?? ?? ) and other substances. Since concomitant bacteria possibly existing in root of farm products can be considered to contribute to LPS of plant origin, a count was taken of bacterial cells both dead and alive. This count revealed that some LPS were derived from concomitant bacteria which had probably come from root. Few concomitant bacterial cells were found in seaweed, while stem-root contained enough bacterial cells. Three predominant bacteria have been isolated and identified; Pantoea agglomerans, Enterobacter cloacae, and Serratia ficaria. These LPSs were purified and their chemical compositions were examined. They are similar to that of Escherichia coli except that their molecular sizes are smaller. Since LPS is non-toxic when taken orally or percutaneously, these LPSs may also be advantageous in the cure of inrtactable diseases.View full abstractDownload PDF (795K) -
Hiroyuki INAGAWA, Fumiko SAITOH, Makoto IGUCHI, Takashi NISHIZAWA, Tak ...1992 Volume 40 Issue 4 Pages 998-1000
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSProtective effect of lipopolysaccharide (LPS) from various sources on gastric ulcer has been examined in mice using parenteral as well as oral route. Ulcer is induced by indomethacin, stress or alcohol. LPS was prepared from 6 species of bacteria (Escherichia coli, pantoea agglomerans, Serratia ficaria, Enterobacter cloacae, Bordetella pertusis, Alcaligenes faecalis) and from wheat flours. When administered intravenously, LPS of Pantoea agglomerans was the most effective among other LPS examined. Lipopolysaccharide of wheat flour (LPSw) showed a significantly protective effect by the oral route, especially when given ad libitum in drinking water to mice.View full abstractDownload PDF (660K) -
Takafumi OKUTOMI, Takashi NISHIZAWA, Hiroyuki INAGAWA, Akinobu MORIKAW ...1992 Volume 40 Issue 4 Pages 1001-1003
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe effect of LPSw, a lipopolysaccharide from a water extract of wheat flour, on pain response was investigated using an acetic acid-induced writhing test in mice. LPSw inhibited writhing dose-dependently in the range of 10 ng-10 μg/mouse i.v. This effect reached its maximum 1.5-3 h after the LPSw inoculation and was detectable even after 8 h. The analgesic effect of LPSw was inhibited by i.v. injection of naloxone and also β-endorphin was detected in serum and brain tissue following injection of LPSw.Preliminary clinical trials were done in which LPSw was administered percutaneously to relieve the pain of patients with herpes. The results showed that pain was relieved by this application. LPSw may be the best analgesic drug so far known, since it induces the endogenous mediator of analgesia, β-endorphin.View full abstractDownload PDF (565K) -
Makoto IGUCHI, Hiroyuki INAGAWA, Takashi NISHIZAWA, Takafumi OKUTOMI, ...1992 Volume 40 Issue 4 Pages 1004-1006
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA lipopolysaccharide from wheat flour (LPSw) which was isolated and characterized is shown to exert definitely a suppressive effect on incidence of type 1 diabetes in mice. Therapeutic effect on type 2 diabetes in patients was also obtained, though only from preliminaly results. The percutaneous route of administration is most favorable. The important role that precursor tumor necrosis factor, free or cell bound, may play in this mechanism is discussed.View full abstractDownload PDF (491K) -
Hirofumi SAMEMOTO, Ichimaro YAMADA, Tomoko YATA, Kenji OGAWA1992 Volume 40 Issue 4 Pages 1007-1010
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA powder coating mixture was investigated with a view toward improving the dissolution property of the anxiolytic 2-(4-chlorophenyl)-5, 6-dihydro-[1]benzo-thiepino-[5, 4-c]-pyridazin-3(2H)-one 7-oxide (1), which was barely water soluble. The powder coating mixture in various ratios of 1 and cornstarch was prepared in an automated mortar. Among these mixtures, at the cptimum ratio of 1 and cornstarch (2 : 1, 67% drug content), the powder coating mixture gave a maximized effect for solubilizing 1 on the bases of stability and solubility. Conventional granules were made from the 67% powder coating mixture. The granules showed an excellent absorption profile in beagle dogs. The mechanism of the solubilizing effect resulting from a phatmaceutical process was also discussed.View full abstractDownload PDF (1066K) -
Junzo NAKAMURA, Michihiro KATAYAMA, Koyo NISHIDA, Hitoshi SASAKI1992 Volume 40 Issue 4 Pages 1011-1015
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAn assessment of 5-fluorouracil (5-FU)-induced mucosal damage in vivo by measuring the metabolism of salicylamide (SAM) was investigated in rabbit intestine. The mucosal damage in the intestine 48 h after oral administration of 5-FU (30 mg/kg) was examined using a scanning electron microscope. By the oral pretreatment with 5-FU, the morphological changes of jejunal and ileal mucosa were recognized compared with the control. The intestinal first-pass metabolism of SAM was studied using in situ intestinal sacs with complete mesenteric venous blood collection. The appearance of both SAM and its metabolites into the mesenteric venous blood was measured directly by cannulating the mesenteric vein of exposed intestine and collecting all venous blood draining from the absorbing region. Following oral pretreatment with 5-FU, the appearance of SAM glucuronide (SAMG) in the mesenteric venous blood was significantly increased. The increased blood concentration of SAMG following intraduodenal administration of SAM in vivo was observed in rabbits pretreated with 5-FU orally. However, the blood concentration of SAMG after intravenous administration of SAM was not increased compared with the control. These findings suggest that the change in intestinal first-pass metabolism of SAM may be due to the intestinal mucosal damage by oral pretreatment with 5-FU. The alteration of intestinal first-pass metabolism of a marker compound may be utilized for the assessment of intestinal mucosal damage in vivo.View full abstractDownload PDF (1948K) -
Shiro YOSHIOKA, Yoshiko BANNO, Yukio OKANO, Kazuo OHKI, Yuzo MIZUKAMI1992 Volume 40 Issue 4 Pages 1016-1021
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe investigated the distribution and fate of liposomes after their intravenous injection into a mouse. Liposomes were composed of dimyristoylphosphatidylcholine, cholesterol and dicetylphosphate (7 : 2 : 1, molar ratio) with or without lactosylceramide. They were characterized as small unilamellar vesicles, approximately 100 nm in diameter, using gel-exclusion chromatography on a Sephacryl S-1000, freeze-fracture electron microscope and dynamic light scattering method. Liposomes were very stable in serum as seen by the results of leakage of the entrapped marker and electrophoresis experiments. We demonstrated that liposomes were internalized by way of an endocytotic process via coated vesicles detected in the electron microscope. The increase in liver uptake of lactosylceramide-bearing liposomes was mostly accounted for by enhanced uptake in the parenchymal cells, while uptake by non-parenchymal cells was only slightly increased. This observation supported the notion that a galactose-specific receptor was involved in liver uptake of lactosylceramide liposomes. The lactosylceramide-bearing liposomes were preferentially recovered in the liver and were found to first be predominantly localized in the mitochondria-lysosomal fraction. They were then decomposed by lysosomal enzymes, and the hydrolyzed components were reincorporated into membrane phospholipids in the microsomal fraction. At the same time, a rapid and reversible exchange of phosphatidylcholine between microsomes and mitochondria was demonstrated.View full abstractDownload PDF (1505K) -
Masafumi GOTO, Junzo HIROSE, Masahide NOJI, Keun-Im LEE, Reiko SAITO, ...1992 Volume 40 Issue 4 Pages 1022-1024
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe absolute configuration of the anti-tumor complex trans(OH)-Pt(OH)2(malonato)(1R, 2R-cyclohexanediamine) was determined by X-ray anomalous scattering technique. The final unit cell was monoclinic, space group P21 with a = 9.142Å, b = 7.788Å, c = 11.946Å, β = 96.48°, Z = 2. The crystal structure was determined by direct method and difference Fourier synthesis, and refined to R = 0.025 and Rw = 0.033 based on 2768 independent reflections. The platinum atom has roughly octahedral coordination. The cyclohexane ring has the expected chair configuration, with two amino groups in equatorial positions while the malonato ligand, in contrast, shows a boat conformation for six membered Pt O-C-C-C-O ring.View full abstractDownload PDF (515K) -
Hiroaki YAMAZAKI, Hidenori HARADA, Kennichi MATSUZAKI, Tetsuo WATANABE ...1992 Volume 40 Issue 4 Pages 1025-1028
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS5-Methyl-2, 3-dioxo-2H, 4H-1, 4-thiazine (7) was obtained by the oxidation of 5-methyl-2H-1, 4-thiazin-3(4H)-one (5) with m-chloroperbenzoic acid in MeOH, followed by acid hydrolysis of the resulting 2, 2-dimethoxy-1, 4-thiazine (6). 3-Chloro-2-oxo-1, 4-thiazine (10), which was obtained from 7 by heating with phosphorous oxychloride, reacted with various nucleophiles to give 3-substituted 2-oxo-1, 4-thiazines (11a-y). Some of these 2-oxo-1, 4-thiazines, 11a-b, e, o and r-s, showed a protective effect against endotoxin shock in D-galactosamine-sensitized mice.View full abstractDownload PDF (562K) -
Yoshio OKADA, Shigeru NAKAYAMA, Shin IGUCHI, Yutaka KIKUCHI, Masachika ...1992 Volume 40 Issue 4 Pages 1029-1032
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSDownload PDF (714K) -
Yoshisuke TSUDA, Yoshiyuki SATO, Kyoko KAKIMOTO, Kimihiro KANEMITSU1992 Volume 40 Issue 4 Pages 1033-1036
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSCyclic thionocarbonates and thionolactones, when heated with 1.0-1.5 mol eq of dibutyltin oxide or bistributyltin oxide in dioxane, gave the corresponding carbonates and lactones in satisfactory yields, respectively.View full abstractDownload PDF (659K) -
Mitsuko KATO, Shohei SUZUKI, Miyako SHIMAMURA, Koohei NOZAWA, Ken-ichi ...1992 Volume 40 Issue 4 Pages 1037-1038
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSElectrochemical methoxylation at the active methylene group of phenylacetates and 1-naphthaleneacetate was conducted successfully at room temperature, in methanol containing potassium iodide as an electron carrier and solium methoxide as a bade and a methoxylating agent. Along with the mono-methoxylated products, dimethoxy, hydroxy, and oxo derivatives as well as the dimers (succinates) were produced as by-products.View full abstractDownload PDF (439K) -
Akemi TOYOTA(nee MIZUTANI), Nobuya KATAGIRI, Chikara KANEKO1992 Volume 40 Issue 4 Pages 1039-1041
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA general procedure has been developed for the preparetion of 9-alkylated adenines by the Mitsunobu reaction between 6-chloropurine and several alcohols, followed by the replacement of the chlorine with ammonia. A lesser amount of the 7-alkylpurines was also obtained, irrespective of the alcohol used.View full abstractDownload PDF (539K) -
Kunio HIGASHI, Kiyoshi NAKAYAMA, Emiko SHIOYA, Tsuneo KUSAMA1992 Volume 40 Issue 4 Pages 1042-1043
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSWe have succeeded in developing a novel glycosidation catalyzed by a combination of trimethylsilyl bromide (TMSBr) and a Lewis acid using simple O-glycosides as glycosyl donors. Treatment of benzyl 2-deozy-2-tri-chloroethoxycarbonylamino-D-glucopyranoside with TMSBr and zinc bromide in the presence of glycosyl acceptors gave α-O-glycosides in moderate to high yields. Zinc triflate and tin(II)triflate were also found to be effective as the Lewis acid. This new methodology is applicable to methyl D-glucopyranoside.View full abstractDownload PDF (460K) -
Yasuyiki KITA, Norio SHIBATA, Naoki YOSHIDA, Takashi TOHJO1992 Volume 40 Issue 4 Pages 1044-1046
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS4-Sulfinylazetidin-2-ones were reacted with various types of tributyltin alkoxides in the presence of a catalytic amount of trimethylsilyltrifluoromethanesulfonate to give the corresponding trans-alkoxyazetidin-2-ones in high yields.View full abstractDownload PDF (549K) -
Tominari CHOSHI, Shigenori HORIMOTO, Ching Y. WANG, Hisamitsu NAGASE, ...1992 Volume 40 Issue 4 Pages 1047-1049
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwenty dibenzoylmethanes with methyl, methoxy, bromo, chloro, or fluoro substitution on either one or both benzene rings were synthesized and assayed for inhibition of the mutagenicity of 2-nitrofluorene in S. typhimurium TA98. 2, 2-Dimethoxy, 3, 3-dimethoxy and 3, 3, 4, 4-tetramethoxydibenzoylmethane was as active as dibenzoylmethane. None of the halogen-substituted dibenzoylmethanes were active. These results demonstrate that dibenzoylmethanes can inhibit the mutagenicity of 2-nitrofluorene, and that modifications made on the benzene rings of dibenzoylmethane cannot enhance the antimutagencity of this parent compound.View full abstractDownload PDF (647K) -
Hideji ITOKAWA, Hiroshi MORITA, Koichi TAKEYA1992 Volume 40 Issue 4 Pages 1050-1052
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSUsing high-resolution proton nuclear magnetic resonance (1H-NMR) and carbon-13 nuclear magnetic resonance (13C-NMR) experiments, we have assigned three discernible configurational isomers observed in dimethyl sulfoxide-d6 (DNSO-d6) for an antitumor cyclic hexapeptide, RA-VII isolated from Rubia cordifolia. The largest isomer, amounting to 64%, has been assigned as conformer A with only a cis configuration between Tyr-5 and Tyr-6. The second configurational isomer, accounting for 32%, has adopted cis configurations between both Tyr-5 and Tyr-6 and between Ala-2 and Tyr-3. The third isomer, amounting to 4%, was determined to have cis configurations for all of the three N-methyl amide bonds.View full abstractDownload PDF (499K) -
Hideji ITOKAWA, Etsuko KISHI, Hiroshi MORITA, Koichi TAKEYA1992 Volume 40 Issue 4 Pages 1053-1055
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew cytostatic quassinoids, 6α-hydroxyeurycomalactone (1), longilactone (2) and 14, 15β-dihydroxyklaineanone (3) were isolated from the woods of Eurycoma longifolia (Simaroubaceae) with three cytotoxic quassinoids, 11-dehydroklaineanone (4), eurycomalactone (5) and 5, 6-dehydroeurycomalactone (6), and with seven cytotoxic tirucallane-type triterpenes, niloticin (7), dihydroniloticin (8), piscidinol A (9), bourjotinolone A (10), 3-episapelin A (11), melianone (12) and hispidone (13). All of them showed potent cytotoxic activity against P388 and KB cells.View full abstractDownload PDF (581K) -
Dong-Hyun KIM, Hae-Kyung YOON, Motoaki KOIZUMI, Kyoichi KOBASHI1992 Volume 40 Issue 4 Pages 1056-1057
Published: April 25, 1992
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel sulfotransferase which was isolated from Eubacterium A-44, a human intestinal bacterium, sulfated phenolic antibiotics, such as amoxicillin, ceaodroxil and cefoperazone. The Km values of sulfotransferase for these antibiotics were 6.9, 4.3 and 22.2 mM, respectively. The Vmax values were 8.3, 3.3 and 1.6 μmol/min/mg protein. The optimal pH of the enzyme was 9.0, a weakly alkaline region. The antibacterial activity of amoxicillin was not altered by enzymic sulfation of the phenolic hydroxyl group.View full abstractDownload PDF (457K)