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Volume 43, Issue 5
Displaying 1-30 of 30 articles from this issue
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Noriyuki YAMAOTSU, Ikuo MORIGUCHI, Shuichi HIRONO1995 Volume 43 Issue 5 Pages 717-721
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIt has been accepted that free energy differences between amino acids calculated using computer simulations are in good agreement with the corresponding experimental values. In recent years, however, Sharp et al. [Biochemistry, 30, 9686 (1991)] pointed out that the experimental solvation free energies had been underestimated and suggested reevaluation of the extent of agreement between the experiment and computer simulations. We calculated the free energy differences of transfer from vapor to water between neutral amino acids using molecular dynamics/free energy perturbation method and compared the calculated values (ΔΔGcalc) with both the uncorrected values (ΔΔGuncorr) obtained by Wolfenden et al. [Science, 206, 575 (1979); Biochemistry, 20, 849 (1981)] and the corrected values (ΔΔGcorr) by Sharp et al. considering the effect of solute-solvent size differences. For the uncorrected values, the correlation coefficient was r=0.938 and the simple regression equation was ΔΔGuncorr=0.823ΔΔGcalc-0.235. For the corrected values, the correlation coefficient and the simple regression equation were r=0.987 and ΔΔGcorr=1.042ΔΔGcalc-0.172, respectively. It was shown that the calculated values are in better agreement with the corrected values than with the uncorrected values.View full abstractDownload PDF (614K) -
Kimio HIGASHIYAMA, Hideki FUJIKURA, Hiroshi TAKAHASHI1995 Volume 43 Issue 5 Pages 722-728
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe reaction of organocerium reagents with chiral aliphatic imines derived from (R)-O-methylphenylglycinol afforded the corresponding amines with high diastereoselectivity. In contrast, the reaction of Grignard reagents with chiral 2-alkyl-1, 3-oxazolidines derived from (R)-N-methylphenylglycinol afforded the amines with changeover in diastereoselectivity.View full abstractDownload PDF (1152K) -
Takao TANAHASHI, Atsuko SHIMADA, Naotaka NAGAKURA, Kenichiro INOUE, Ma ...1995 Volume 43 Issue 5 Pages 729-733
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSix new iridoid glucosides, jashemslosides A-D (2-5), 6'-O-trans-p-coumaroylloganin (6) and 6'-O-cis-p-coumaroylloganin (7), were isolated from the leaves of Jasminum hemsleyi, together with the known glycosides, loganin, 7-dehydrologanin, jasminoside, 10-hydroxyoleoside dimethyl ester and lariciresinol-4-O-β-D-glucoside. The structures of the new glucosides 2-7, which contain a menthiafolic acid unit or p-coumaroyl group in addition to the loganin moiety, were elucidated by spectroscopic and chemical studies. Chirospecific HPLC analysis of the monoterpenic acid derivatives prepared from 2 and 3 revealed that each of the new compounds was a mixture of two inseparable diastereoisomers.View full abstractDownload PDF (881K) -
Yutaka OZAKI, Ayako KUBO, Kyouko OKAMURA, Sang-Won KIM1995 Volume 43 Issue 5 Pages 734-737
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA new procedure using lithium chloride in hexamethylphosphoramide was found to be useful for the synthesis of Michael-type adducts and cyclic enones. Selectivity for the two products could be controlled by altering the reaction temperature employed. The urea-type solvents were also examined instead of hexamethylphosphoramide.View full abstractDownload PDF (715K) -
Shunji SAKURABA, Hisashi TAKAHASHI, Hideo TAKEDA, Kazuo ACHIWA1995 Volume 43 Issue 5 Pages 738-747
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThe complexes of pyrrolidine bisphosphine ligands (CPMs) with rhodium (I) were found to be efficient catalysts for asymmetric hydrogenation of α-amino ketone hydrochloride derivatives. Utilizing this methodology, we have developed efficient asymmetric syntheses of the optically active β-amino alcohols, phenylephrine, levamisole, carnitine and propranolol.View full abstractDownload PDF (1342K) -
Shunji SAKURABA, Kazuo ACHIWA1995 Volume 43 Issue 5 Pages 748-753
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSN-(Methylcarbamoyl)-4-(dicyclohexylphosphino)-2-[(diphenylphosphino)methyl]pyrrolidine (MCCPM)- and N-(tert-butoxycarbonyl)-4-(dicyclohexylphosphino)-2-[(diphenylphosphino)methyl]pyrrolidine (BCPM)-rhodium(I) complexes werer efficient catalysts for asymmetric hydrogenations of β- and γ-amino ketone hydrochloride derivatives. Utilizing this methodology, we have developed efficient syntheses of fluoxetine and eprozinol from intermediate optically active amino alcohols.View full abstractDownload PDF (898K) -
Alangionosides G-M : Glycosides of Megastigmane Derivatives from the Leaves of Alangium premnifoliumHideaki OTSUKA, Masami YAO, Kenji KAMADA, Yoshio TAKEDA1995 Volume 43 Issue 5 Pages 754-759
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSPhytochemical investigation of the 1-BuOH-soluble fraction of the MeOH extract of Alangium premnifolium resulted in the isolation of ten megastigmane glycosides, of which, two, (6R, 9R)-3-oxo-α-ionol apiofuranosylglucopyranoside and roseoside with (6S, 9R)-blumeol A as an aglycone were known. The structures of the eight new compounds were determined by spectroscopic methods.View full abstractDownload PDF (968K) -
Chikara KANEKO, Jun CHIBA, Akemi TOYOTA, Masayuki SATO1995 Volume 43 Issue 5 Pages 760-765
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSReaction of molecular fluorine with unsaturated azlactones derived from appropriate aldehydes (or ketones) and benzoylglycine afforded the difluorinated adducts. The reductive amination reaction of the β-fluorinated α-oxoalkanoic acids obtained from the adducts by basic hydrolysis gave erythro-β-fluorinated aliphatic α-amino acids. The same reactions, when applied to methyl 3-phenyl-2-benzoylaminoacrylate, afforded the corresponding aromatic amino acid. Hence, the entire sequence provides a general method for the synthesis of erythro-β-fluorinated α-amino acids.View full abstractDownload PDF (900K) -
Tutomu ISHIKAWA, Atsuya TAKAMI, Masatoshi ABE, Ih-Sheng CHEN, Takashi ...1995 Volume 43 Issue 5 Pages 766-770
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSChelerythrine-type oxobenzo[c]phenanthridine bases were effectively synthesized by the action of 1, 3-dimethoxy-benzene on 2-(2-methoxycarbonylphenyl)-1-(N-methylformamido)naphthalenes in the presence of phosphorus oxychloride. The N-deformylation based on the Vilsmeier-Haack reaction is also discussed.View full abstractDownload PDF (814K) -
Mamoru KOEDA, Yoshinobu AOKI, Nobuko SAKURAI, Masahiro NAGAI1995 Volume 43 Issue 5 Pages 771-776
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree new cyclolanostanol xylosides were isolated from a batch of commercial Cimicifuga Rhizome, cimicifugoside H-1 (1), C35H52O9, mp 260-262°C, [α]D -43.5°, cimicifugoside H-2 (2), C35H54O10, mp 227-229°C, [α]D -38.8°, and cimicifugoside H-5 (3), C35H52O10, mp 262-264°C, [α]D -22.9°, together with known glycosides, actein and 27-deoxyactein. Their structures were determined on the basis of chemical and spectrometric evidence including an X-ray crystallographic analysis. The structure of cimicifugoside H-1 (1) was established as (20R, 24R)-24, 25-epoxy-11β-hydroxy-3-β-(β-D-xylopyranosyloxy)-9, 19-cyclolanost-7-ene-16, 23-dione. Cimicifugoside H-5 (3) is the 15-hydroxylated derivative of 1. Since 1 changed into cimicifugoside H-2 (2) on treatment with p-toluenesulfonic acid, 2 has a 24R, 25-diol structure derived from 1 by opening its epoxy ring.View full abstractDownload PDF (866K) -
Naoki SAITO, Shunji HARADA, Masayo NISHIDA, Izumi INOUYE, Akinori KUBO1995 Volume 43 Issue 5 Pages 777-782
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTreatment of (-)-saframycin A (1a) with selenium oxide in acetic acid afforded (-)-saframycin G (1g), and a catalytic reduction and regionselective oxidation sequence afforded the saframycin Mx type compound (3). We applied this methodology to the transformation of (±)-5-hydroxysaframycin B (11) to the hydroquinone (1e). Acetylation of 1e with acetic anhydride in pyridine gave the triacetate (13), which is identical with the triacetyl derivative of natural saframycin E.View full abstractDownload PDF (1049K) -
Yutaka KAWASHIMA, Akiyo HORIGUCHI, Minoru TAGUCHI, Yoshimi TUYUKI, Yas ...1995 Volume 43 Issue 5 Pages 783-787
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA series of 1, 2, 3, 4-tetrahydro-β-carbolines has been synthesized and evaluated for cerebral protecting effects against lipid peroxidation and potassium cyanide intoxication in mice. Most of the compounds synthesized had potent effects against lipid peroxidation. Among them, 1-(3, 5-dimethoxyphenyl)-2-propyl-1, 2, 3, 4-tetrahydro-β-carboline (22) was found to have a combination of potent effects against both lipid peroxidation and potassium cyanide intoxication. Structure-activity relationships are discussed.View full abstractDownload PDF (662K) -
Takashi KOBAYASHI, Teruhiko INOUE, Zyunichiro KITA, Haruo YOSHIYA, Shi ...1995 Volume 43 Issue 5 Pages 788-796
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel 2-amino-1, 4-dihydropyridine derivatives, which contain nitroxy-alkoxycarbonyl groups at the 3- and/or 5-position, were synthesized and their pharmaceutical effect was evaluated in spontaneously hypertensive rats. The structure-activity relationships are discussed in terms of potency, onset-rapidity, and duration of antihypertensive activity. Remarkably prolonged duration of antihypertensive action was observed when a tertiary amino group was introduced on either side of an ester chain.View full abstractDownload PDF (1259K) -
Takashi KOBAYASHI, Teruhiko INOUE, Shigeyoshi NISHINO, Yoshimi FUJIHAR ...1995 Volume 43 Issue 5 Pages 797-817
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel 2-amino-1, 4-dihydropyridine derivatives I, which contain N, N-dialkylaminoalkoxycarbonyl groups at the 3- and/or 5-position, were synthesized and their antihypertensive effects were evaluated in spontaneously hypertensive rats. Remarkably prolonged duration of antihypertensive action was observed when a tertiary amino group was introduced into either the 3- or 5-ester side-chain of the 1, 4-dihydropyridine ring. In particular, the compounds containing cyclic amino moieties at the 3-position showed greater potency than those with acyclic amino moieties. Chemical modification studies indicated that the two ester side-chains of 1, 4-dihydropyridine at the 3- and 5-position might function in a different manner in relation to the antihypertensive activities. 3-(1-Benzhydrylazetidin-3-yl) 5-isopropyl 2-amino-1, 4-dihydro-6-methyl-4-(3-nitrophenyl)-3, 5-pyridine-dicarboxylate, I-43 (CS-905), exhibited potent and long-lasting antihypertensive effects with gradual onset of action, and is a promising candidate as an antihypertensive drug.View full abstractDownload PDF (2058K) -
Koji OHSUMI, Kazuo OHISHI, Yoshihiro MORINAGA, Ryusuke NAKAGAWA, Yasuy ...1995 Volume 43 Issue 5 Pages 818-828
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNew N-alkylated 1, 4-dihydropyridine derivatives were synthesized and their ability to overcome multidrug resistance was examined in vincristine-resistant P388 cells (P388/VCR cells). Compounds that possessed an arylalkyl substituent on the dihydropyridine ring nitrogen were more potent than verapamil in potentiating the cytotoxicity of vincristine against P388/VCR cells. However, neither drug effectively enhanced the antitumor activity of vincristine in tumor-bearing mice. Introduction of basic nitrogen-containing substituents on the side chain of 1, 4-dihydropyridines gave improved activity in vitro and in vivo. The piperazine derivative 12c and 12o were more than 10 times as potent as verapamil in vitro. Four compounds selected for in vivo testing showed superior antitumor activity in P388/VCR-bearing mice in combination with vincristine. The structure-activity relationships of the compounds are discussed.View full abstractDownload PDF (1281K) -
Yoshihiko KOTAKE, Tatsuo OKAUCHI, Atsumi IIJIMA, Kentaro YOSHIMATSU, H ...1995 Volume 43 Issue 5 Pages 829-841
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSStructural modifications of an extremely potent inhibitor of dihydrofolate reductase (DHFR) activity and tumor cell growth, N-[4-[3-(2, 4-diamino-6, 7-dihydro-5H-cyclopenta[d]pyrimidin-5-yl)propyl]benzoyl]-L-glutamic acid (1), have led to the synthesis of new cyclopenta[d]pyrimidine-based antifolates, including those with low alkyl substituted trimethylene bridges (2a, b) and isosterically modified bridges (ethyleneoxa, 2c; ethyleneamino, 2d; the N-methyl- and N-ethyl derivatives of 2d, 2e, f) and those in which the benzene ring of 1 has been replaced by heterocyclic isosters (indole, 2g; indoline, 2h; thiophene, 2i). These new analogs are highly potent as DHFR and cell growth inhibitors, and most of them are more potent than methotrexate (MTX) and 10-ethyl-10-deazapterin (10-EDAM) in inhibiting tumor cell growth (P388 MTX-sensitive and MTX-resistant, colon 26 and KB) on 72h drug exposure. Among them, 2a (the 10-methyl derivative of 1) and 2i were most potent, being 2- to 3-fold more potent than 10-EDAM. On 4h drug exposure, the growth-inhibitory activity of these analogs was radically influenced by even minor structural changes. Compounds 1, 2a-e, g-i were much more cytotoxic in colon 26 cell line than were MTX and 10-EDAM, with 2d and 2i being most potent, followed by 2a. Structure-activity relationships and their possible significance are discussed.View full abstractDownload PDF (1949K) -
Shin-ichi TSUKAMOTO, Mitsuo FUJII, Tomoyuki YASUNAGA, Koyo MATSUDA1995 Volume 43 Issue 5 Pages 842-852
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS2, 8-Dimethyl-1-oxa-8-azaspiro[4.5]decan-3-one (17), designed by incorporating the tetrahydrofuran ring moiety of muscarone into an 8-azaspiro[4.5]decane skeleton, and related 1-oxa-8-azaspiro[4.5]decanes were synthesized and assessed as M1 muscarinic agonists for the symptomatic treatment of dementia of Alzheimer's type. The compounds were tested for central muscarinic M1 and M2 receptor affinity and in vivo muscarinic activities : namely, amelioration of scopolamine-induced impairment in rat passive avoidance tasks, and induction of hypothermia, tremor, and salivary secretion. Compound 17 exhibited potent muscarinic activities in vitro and in vivo with no selectivity. Systematic modifications of 17 were conducted, and a number of compounds, including the 2-ethyl analogue (18), 3-methylene analogue (29), 3-dithioketal analogues (26, 28), and 3-oxime analogue (37) were found to display preferential affinity for M1 receptors over M2 receptors and, in addition, to exhibit potent antiamnesic activity sufficiently separated from hypothermia-inducing activity, taken as an index of cholinergic side effects, compared with the reference compound RS86 (1). Structure-activity relationships are discussed in comparison with those for muscarone analogues. Of these compounds only two, 2-ethyl-8-methyl-1-oxa-8-azaspiro[4.5]decan-3-one (18) and 2, 8-dimethyl-3-methylene-1-oxa-8-azaspiro[4.5]decane (29), stimulated phosphoinositide hydrolysis in rat hippocampal slices, indicating partial agonistic activity for M1 muscarinic receptors.The optical resolution of 18 and 29 was performed. Eudismic ratios of both compounds in binding affinity were low, but M1 agonist activity resided preferentially in the (-)-isomers. The absolute configuration of (-)-29 was determined by X-ray crystal structure analysis to be S, being the same as that of muscarone. Based on the in vivo selectivity, (-)-29 was selected for clinical studies.View full abstractDownload PDF (1768K) -
Hirokazu TAMAMURA, Tsutomu MURAKAMI, Sankichi HORIUCHI, Keiji SUGIHARA ...1995 Volume 43 Issue 5 Pages 853-858
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSAll disulfide analogs (types I, II and III) of protegrin (PG)-1, an 18-residue antimicrobial peptide having two intramolecular disulfide bonds, were synthesized using regioselective disulfide bond formation. Random air-oxidation of the fully reduced PG-1 formed the type III PG-1. In addition, a type III analog containing an amidated carboxy-terminal residue was also prepared. Each analog showed significant and different antibacterial and anti-human immunodeficiency virus (HIV) activity. Deletion of two disulfide bridges caused a significant decrease in activity.View full abstractDownload PDF (955K) -
Yoko AIDA, Toshio KASAMA, Naoki TAKEUCHI, Seisho TOBINAGA1995 Volume 43 Issue 5 Pages 859-867
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSKhellactones of Peucedanum praeruptorum DUUN, including praeruptorins A (=Pd-Ia, 2) and B (=Pd-II, 11), had an antagonistic effect specifically on platelet aggregation induced by platelet activating factor (PAF) among various aggregating agents examined, and represent a new class of PAF antagonists. We examined the effects of twenty compounds on PAF-induced platelet aggregation and on histamine- and leukotriene D4 (LTD4)-induced contractions in isolated guinea pig ileum. Compounds 2, (±)-cis-3', 4'-diacetylkhellactone (3), (±)-cis-4'-acetyl-3'-crotonoylkhellactone (5), (±)-cis-4'-acetyl-3'-tetrolylkhellactone (6), (±)-cis-4'-acetyl-3'-tigloylkhellactone (7), (±)-cis-4'-acetyl-3'-(2"-methylbutyryl)khellactone (8), (±)-cis-3', 4'-ditigloylkhellactone (10), and 11 all strongly inhibited PAF-induced platelet aggregation. (±)-cis-4'-Acetyl-3'-(2"-methyl-2"-dodecenoyl)khellactone (9), (±)-cis-4'-ethyl-3'-tigloylkhellactone (13), (±)-cis-4'-ethyl-3'-[N-(2"-triethylammonio)ethylcarbamoyl]khellactone iodide (16), (±)-trans-3', 4'-diacetylkhellactone (18), (±)-trans-4'-acetyl-3'-crotonoylkhellactone (19), (±)-trans-4'-acetyl-3'-valerylkhellactone (20), (±)-trans-4'-acetyl-3'-isovalerylkhellactone (21), and (±)-trans-4'-acetyl-3'-tigloylkhellactone (22) were weakly inhibitory. Most of the compounds exhibited noncompetitive antagonist actions on histamine- and LTD4-induced contractions. The potencies of the antagonistic effects on histamine action were in the order 7=22≥2=8=10>6=11=13≥5>19=9 and those on LTD4 action were in the order 6=22=2>10=8>7=9=11≥13. Thus, compounds with potent PAF-antagonistic activities have the following features : cis isomers of khellactone at the C-3' and C-4' positions are more favorable than trans isomers, and the acyl moiety at the C-3' position of khellactone must be of an appropriate molecular size. In the case of histamine- and LTD4-antagonistic activities, both isomers show similar effects and acyl moieties of appropriate size are required at the C-3' and C-4' positions. These results are of interest in regard to the medicinal uses of Peucedanum species as a herbal drug.View full abstractDownload PDF (1218K) -
Masateru ONO, Yasuyuki ITO, Junei KINJYO, Shoji YAHARA, Toshihiro NOHA ...1995 Volume 43 Issue 5 Pages 868-871
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSFour new glycosides of stibene trimer, termed foeniculosides I, II, III and IV, were isolated from Foeniculi Fructus (fruit of Foeniculum vulgare MILLER) along with two known stilbene trimers, miyabenol C and cis-miyabenol C. The structures of foeniculosides I, II, III and IV were characterized as 11a-O-β-D-glucopyranoside, 13b-O-β-D-glucopyranoside, 11a, 13b-di-O-β-D-glucopyranoside, 11a, 13b, 13c-tri-O-β-D-glucopyranoside of cis-miyabenol C, respectively, on the basis of chemical and spectroscopic data.View full abstractDownload PDF (692K) -
Takehisa HANAWA, Atsushi WATANABE, Takanori TSUCHIYA, Rieko IKOMA, Mas ...1995 Volume 43 Issue 5 Pages 872-876
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSSilk fibroin gel (SFG) containing benfotiamine (BTMP) was prepared. The release behavior of BTMP from SFG was studied as a function of silk fibroin (SF) content and glycerol content, and the influence of the existence of β-cyclodextrin (β-CD) on the physicochemical properties of SFG were investigated. The release rate of BTMP from SFG was retarded by an increase in SF concentration. The addition of β-CD affected both the release properties and rheological properties of the SFG. It was found from the results of the "paddle-bead method" that the release profiles of BTMP from SFG were inversely proportional to the SFG firmness.View full abstractDownload PDF (699K) -
Satoru WATANO, Ikuko WADA, Kei MIYANAMI1995 Volume 43 Issue 5 Pages 877-880
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSIn a previous paper, [Watano et al., Chem. Pharm. Bull., 42, 2338 (1994)], we proposed a simple model which could be used to analyze data of controlled release of a water-soluble drug from spherical particles coated with an aqueous-based system of acrylic copolymer by a tumbling fluidized bed process. The model predicted that the fractional release of drug was related to exponential of release time, and drug release data of several samples prepared with various levels of operational moisture content were studied to determine the effect of this content on film thickness and drug permeability.In this study, to confirm the method's validity, we simulated the drug release rate at various moisture content and coating levels using the proposed model. The simulated results were compared with the experimental data to evaluate the accuracy of the model. The mechanism of aqueous coating was also described using the simulated results.View full abstractDownload PDF (602K) -
Takashi ITOH, Yuji MATSUYA, Hiroshi HASEGAWA, Kazuhiro NAGATA, Mamiko ...1995 Volume 43 Issue 5 Pages 881-883
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSMonocyclic 1, 2, 3-triazines were reacted with ketene silyl acetal or silyl enol ether in the presence of 1-chloroethyl chloroformate to give 5-substituted 2-(1-chloroethoxycarbonyl)-2, 5-dihydrotriazines. These dihydro-adducts were readily oxidized and hydrolyzed with ceric ammonium nitrate in CH3CN/H2O to afford 5-substituted triazines.View full abstractDownload PDF (476K) -
Nobuya KATAGIRI, Masashi MAKINO, Chikara KANEKO1995 Volume 43 Issue 5 Pages 884-886
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSOne of the two primary hydroxyl groups of oxetanocin A was protected selectively with acetyl and o-nitrobenzyl groups using enzymatic and photochemical reactions, respectively. On the basis of 1H-NMR spectroscopy and NOE experiment, 4'-O-protected oxetanocin A was found to take syn conformation in an aprotic solvent irrespective of the kind of protecting group owing to an intramolecular hydrogen bond.View full abstractDownload PDF (502K) -
Akito NAGATSU, Kiyoshi TENMARU, Hidekazu MATSUURA, Nobutoshi MURAKAMI, ...1995 Volume 43 Issue 5 Pages 887-889
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSNovel antioxidants, 5-(3, 4-dihydroxyphenylmethyl)oxazolidine-2, 4-dione (1) and 3-(3, 4-dihydroxyphenyl)lactamide (2), have been isolated from roasted perilla seed. Compound 1 was the first example of non-synthetic oxazolidinedione.View full abstractDownload PDF (474K) -
Keizo MATSUO, Takahiko ARASE1995 Volume 43 Issue 5 Pages 890-892
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESS(+)-Ipomeamarone (1), a furanosesquiterpene isolated from the mold-damaged sweet potato Ipomea batatas as one of the phytoalexins, was synthesized starting from (+)-lactic acid as a chiral source.View full abstractDownload PDF (450K) -
Yoshihiro MIMAKI, Aiko KAMEYAMA, Yutaka SASHIDA, Yoshiyuki MIYATA, Aki ...1995 Volume 43 Issue 5 Pages 893-895
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA novel cinnamoyl-hexahydrodibenzofuran derivative (1) was isolated from the bark of Lindera umbellata. The structure was determined by extensive spectroscopic analysis to be (5aR*, 6R*, 9R*, 9aS*)-4-cinnamoyl-3, 6-dihydroxy-1-methoxy-6-methyl-9-(1-methylethyl)-5a, 6, 7, 8, 9, 9a-hexahydrodibenzofuran. Compound 1 showed potent inhibitory activity on melanin biosynthesis of cultured B-16 melanoma cells without causing any cytotoxicity in the cultured cells or skin irritation in guinea pig.View full abstractDownload PDF (460K) -
Yoshiteru IDA, Yohko SATOH, Masumi KATSUMATA, Miki NAGASAO, Junzo SHOJ ...1995 Volume 43 Issue 5 Pages 896-898
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSTwo novel saponins, achyranthosides C and D, were isolated from Achyranthes fauriei root, and their structures were characterized based on the chemical and spectroscopic evidence.View full abstractDownload PDF (473K) -
Tomihisa OHTA, Mamoru MATSUDA, Toshimitsu TAKAHASHI, Shigeru NAKAJIMA, ...1995 Volume 43 Issue 5 Pages 899-900
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSA chlorinated amino acid was isolated from Amanita vergineoides. The stereostructurer was elucidated as (S)-cis-2-amino-5-chloro-4-pentenoic acid, on the basis of spectroscopic analysis.View full abstractDownload PDF (344K) -
Kou HIROYA, Koji UWAI, Kunio OGASAWARA1995 Volume 43 Issue 5 Pages 901-903
Published: May 15, 1995
Released on J-STAGE: March 31, 2008
JOURNAL FREE ACCESSThree structural analogus of a potent non-opiate analgesic alkaloid epibatidine have been synthesized in optically pure forms in enantio- and diastereo-controlled ways using a chiral 2, 5-cyclohexadiene-1, 4-diol synthon.View full abstractDownload PDF (458K)
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