We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-1. Sixteen phosphate buffered saline (PBS), 8 boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-,-diene-3β,,6β-triol (1). 1 induced ALP activities of MC3T3-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3-1 cells by 1, ergosterol (), ergocalciferol (3), cholesta-3β,,6β-triol (), -dehydrocholesterol () and cholecalciferol (6) were tested. The enzyme activities of MC3T3-1 cells were increased 3.0-fold by 10 μM 1 and .-fold by 10 μM . However, , 3, and 6 did not induce MC3T3-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C- and/or C-6 of 1 and played an important role in their differentiation-inducing activities on MC3T3-1 cells. Furthermore, 1 suppressed induction of MC3T3-1 cell apoptosis by serum starvation.

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In the first part of the present work the interaction of glycophorin with dimyristoylphosphatidylcholine (DMPC) is studied by freeze fracture electron microscopy, densitometry, calorimetry, and 90° static light scattering. An exothermic lipid/protein interaction energy of W_P=190 kJ•mol^-1 was found by application of the well known Van Laar relation for the displacement of the freezing point and the Gibbs-Duhem relationship. Secondly, the effects of + on the lipid/protein interaction were studied. Following + addition a remarkable decoupling of the interaction of the glycophorin head group with the bilayer surface was revealed by densitometry and gold-labeling electron microscopy. It is estimated that about 80% of lipid once disturbed by the adsorption of glycophorin head groups is decoupled after addition of +. Thirdly, the selective interaction of glycophorin with binary lipid mixtures was studied, including the mixtures of DMPC with dimyristoylphosphatidylserine (DMPS) and dilauroylphosphatidylcholine (DLPC), and the mixture of dipalmitoylphosphatidylcholine (DPPC) with DLPC.

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Alfven resonance effects on the evolution of a magnetic island driven by an externally applied perturbation are investigated for rotating plasmas. The simulation results show the importance of Alfven resonance for obtaining a perturbed current profile and estimating a critical value of the external perturbation, beyond which the magnetic island grows rapidly. The nonlinear evolution of the externally driven magnetic island is also investigated at low and high viscosities ν. It is shown that the transition phase accompanying the secondary reconnection at the initial X-point in the driven magnetic island evolution occurs in low resistivity and viscosity plasmas.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the ^116mIn activity. Directional correlations are also measured for 818–1293 and 1097–1293 keV cascades. The M1- mixing ratio δ, and the 0- mixing ratio μ_k are obtained for 818. keV +→2₁⁺ transition to be δ=1.52−

0.22

+0.26, and μ_k≤6.1×10−

4

respectively. The

E

2

branching ratio B(

E

2

;

2₂

+→0_g⁺): B(

E

2

;

2₂

+→2₁⁺): B(

E

2

;

2₂

+→0₁⁺) is determined to be 0.0158:1.0:

5

.86.

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Fourteen-membered bislactones, (-)-Colletol (1) and (+)-Colletodiol (), were synthesized. Reductive ring opening reaction of ethyl ()-(R, R)-,-epoxy--hexenoate (16) with HCO_H-Et_3N in the presence of Pd_(dba)_3CHCl_3-PPh_3 catalyst gave ethyl ()-(R)--hydroxy--hexenoate (17) in % yield. Protection of the hydroxy group gave the ester 18, followed by hydrolysis gave the unsaturated acid 19. The ester 18 was converted to the epoxy unsaturated ester 21 in steps, which was subjected the palladium-catalyzed reductive ring opening reaction with formic acid to give the alcohol having a 1,3-syn diol system in 72% yield. After the ester 23 was converted to the allyl ester 24, the coupling reaction with 19 was carried out to give 25. Deprotection of the alcohol and reductive removal of the allyl ester, followed by cyclization and deprotection gave (-)-Colletol. Nucleophilic ring opening of the oxirane 21 with acetic acid was carried out stereoselectively with retention of stereochemistry to give 28 in % yield, which has the ,,-trihydroxy moiety with different protection. The ester 29 was converted to the allyl ester 30, and coupling with 19 and cyclization as a similar procedure as above gave (+)-Colletodiol after deprotection. The palladium methods for preparing the alcohols from the oxiranes described above are considered to be useful for stereoselective construction of polyols.

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Distribution of bacteria which produce enzyme capable of lysing Str. mutans 49 strain in human dental plaques was investigated on adults of age 20 to . The activity of the enzyme (MLE) produced by an isolated strain (FDC-63) was also investigated. The results obtained are summarized as follows. 1. MLE producing bacteria were detected in 43 samples (37.1%) out of 116 samples of dental plaques obtained from adults of age 20 to . . Twenty four samples had MLE producing bacteria at the rate of over % of total number of bacteria in each sample. 3. The 40 strains isolated were composed of 92.% of Gram positive cocci, .% of Gram negative cocci and % of Gram positive rods. . Most of the isolates (.6%) showed lytic activity against living cells of 49 on GAM agar plates. . The MLE produced by FDC-63 had lytic activity against both living and heat killed cells of 49 under aerobic or anaerobic condition. 6. The activity of the MLE was rather weak against purified cell walls of 49. . Optimal pH in the activity of the MLE was 6.0 and optimal temperature 37℃. The activity of the MLE was lost by heating at 60℃ for 60 min. 8. FDC-63 was identified as Streptococcus milleri.

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3(-ビニル)-6-メチルピリダジノン(1)および 3(-ビニル)-6-メチル-, -ジヒドロピリダジノン()とアクリル酸()のラジカル共重合を行ない,既報の(1)とメタクリル酸メチルとの共重合結果と比較した。
モノマー反応牲比および Q,値は(1)(M1)-(M)系で r1=0.75,r=0.15, Ql=., 1=-0.72,また()(M1)-(M)系に対して r1=O.06, r=O.10, Q1=.05, 1=-1.50となり共重合性にすぐれ,またQ値は(1)の方が大きく,値は()の方が負に大きくなっていた。
生成共重合体の数平均分子量(Mn),あるいはモノマーのIRスペクトルならびにイオン化能力の測定結果,系では水素結合による相互作用が働いていることが示された。

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A mixture of two monoterpenes was obtained as the opisthonotal gland secretion from unidentified Histiogaster sp. A096 (Acari: Acaridae), and their structures were elucidated to be ()-dehydrocitrals[(,)- and (Z,)-3,-dimethyl-,,6-octatrienals] by GC/MS, GC/FT-IR, UV and ¹H-NMR spectra. Both isomers of ()-dehydrocitral prepared by syntheses in steps from 3-methyl--butenal with 34.% yields (based on the ylide) were separated by column chromatography into the (,)- and (Z,)-3,-dimethyl-,,6-octatrienal. Mass spectra together with GC retention times of the purified natural ()-dehydrocitrals were identical with those of synthetic (,)-3,-dimethyl-,,6-octatrienal and (Z,)-3,-dimethyl-,,6-octatrienal. The geometry at the -C position of both synthetic ()-dehydrocitrals was confirmed by NOESY analyses. This is the first identification of ()-dehydrocitrals from the animal kingdom.

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Callipeltin A (1) is a cyclodepsipeptide from water sponge collected at New Caledonia. This compound shows anti-HIV and cytotoxic activities against KB and P388 cells and contains three new amino acid residues. β-methoxytyrosine (β-MeOTyr) (), (R,3R,S)--amino--guanidino-,-3-dihydroxyheptanoic acid (AGDHE) (), (3S,R)-3,-dimethyl-L-glutamine (diMeGln) (6). In addition, two new truncated open-chain derivatives of Callipeltin A (1), named Callipeltin D () and (3) were isolated. The unique structure and intriguing biological activities of this compound led us to explore total synthesis of Callipeltin A (1) and to elucidate stereochemistry of β-MeOTyr (). We started to synthesize Callipeltin (3) which contains β-MeOTyr (). In order to synthesize four stereoisomer of β-MeOTyr (), we attempted Evans anti or syn-Aldol reaction as a key step. Evans direct anti-aldol reaction with chiral benzyloxazolidinones (8) and p-hydroxy benzaldehyde (9) promoted by catalytic amounts of MgCl_ in the presence of triethylamine and chlorotrimethylsilane. This proceder provide 3:1 diastereoselelctivity and 70% yield of isolated anti-aldol product (10). And Enolizalion of isocyanate oxazolidinone (13) with di-n-butylboryl trifrate and diisopropylethylamine followed by treatment with aldehyde 8 afford syn-aldol product 14 affording 88% yield and 1: anti: sin diastereomeric ratio. On the other hand, we tried Sharpless Asymmetric dihydroxylation (AD) and Aminohydroxylation () to give all four stereoisomers of β-MeOTyr. Treatment of olefin (18) with AD-mix α provided diol (19) and the α position alcohol of 19 was converted to sulfone regioselectively followed by azidation and treatment of 20 with PPh_3 to afford aziridine (21). Addition of aziridine (21) and BF_3・Et_O in methanol produced α-amino β-methoxy adduct (). reaction protocol with t-butylcarbamate was successfully applied to afford desired in single step. Now we construct Callipeltin to determine absolute stereochemistry of β-MeOTyr (). In addition, we report the synthesis of diMeGln (6) and (R,3R,S)-3-hydroxy---6-trimethyl hepanoic acid ().

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