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The palladium catalyzed nucleophilic substitution of alpha-bromo-alpha,alpha-difluoroallyl derivatives turned out to be an efficient method for the preparation of several fluorinated organic molecules. Several soft carbon nucleophiles regioselectively reacted with 3-bromo-3,3-difluoropropene (BDFP) to give the 3-substituted 1,1-difluoroalkenes. Phenylzinc chloride and tributylphenyltin afforded 1-fluoro-1,3-diphenylpropene. The radical bromination of 3-substituted 1,1-difluoroalkenes provided 1-substituted BDFPs, and a 1-substituted BDFP reacted with carbon nucleophiles to give 1,3-disubstituted 3,3-difluoroalkenes. For the reaction of nitrogen nucleophiles with BDFP, an amine and the sodium salts of the carbamates reacted with BDFP at the gamma-position. However, the sodium salts of the sulfoneamide predominantly attacked at the alpha-position.

Diethylaminosulfur trifluoride reacted with cyclic ketoximes bearing substituent(s) that can stabilize a carbocation to cause fluorinative fragmentation, affording fluorinated carbonitrile. Ketoximes lacking such substituents afforded complex mixtures. However, the introduction of a sulfur functionality, which can stabilize a carbocation and can be easily removed from the reaction products, into the ketoxime was effective for producing the fluorinative fragmentation.

Enzymatic hydrolyses were described for three variants of glycosidic conjugated bile acids with one beta-glucuronidase (Helix pomatia), three beta-glucosidase (almonds, sweet almonds, and Escherichia coli), and four beta-N-acetylglucosaminidase (jack beans, bovine kidney, human placenta, and Diplococcus pneumoniae) preparations. The substrates include the beta-glucuronide, beta-glucoside, and beta-N-acetylglucosaminide conjugates of bile acids related to hyodeoxycholic, murideoxycholic, chenodeoxycholic, and ursodeoxycholic acids possessing a sugar moiety at position C-3, C-6 or C-7. The comparative abilities and optimal conditions for the beta-glycosidases to catalyze the hydrolyses of the substrates were clarified by changing pHs and incubation times. Hydrolysis rates of the bile acid glycosides with beta-glycosidase treatments were influenced by both the source of the enzyme preparations and the conjugated position of a sugar moiety in the substrates, and the 3-glucoside and 3-N-acetylglucosaminide conjugates were usually hydrolyzed more efficiently than their corresponding 6- and 7-analogs. Escherichia coli and jack bean enzymes were chosen to hydrolyse the glucosidic and N-acetylglucosaminidic conjugated bile acids, respectively.

Five tridecapeptide lactones, named theonellapeptolides Ia (1), Ib (2), Ic (3), Id (4), and Ie (5), were isolated from the Okinawan marine sponge Theonella swinhoei. Following the structure elucidation of theonellapeptolide Id (4), the structures of theonellapeptolides Ia (1), Ib (2), Ic (3), and Ie (5) were determined on the basis of chemical and physicochemical evidence including high performance liquid chromatography and circular dichroism combined analysis of the amino acid compositions. Theonellapeptolides Ib (2), Ic (3), Id (4), and Ie (5) exhibit moderate cytotoxic activity towards for L1210 in vitro (IC50 1.6, 1.3, 2.4, and 1.4 micrograms/ml, respectively), and theonellapeptolide Ie (5) exhibits ion-transport activities for Na+ and K+ ions.

The 4 beta-hydroxylated derivatives of lithocholic, deoxycholic, chenodeoxycholic, and cholic acids were synthesized from their respective parent compounds. The principal reactions employed were 1) beta-face cis-dihydroxylation of delta 3 intermediates with osmium tetroxide-N-methylmorpholine N-oxide, 2) selective cathylation of vicinal 3 beta,4 beta-diols followed by oxidation of the resulting 4 beta-monocathylates, or direct selective oxidation at C-3 of 3 beta,4 beta-diols with pyridinium chlorochromate, and 3) stereoselective reduction of the 3-oxo compounds with tert-butylamine-borane complex. The results of analysis of the prepared 4 beta-hydroxylated bile acids with a diequatorial trans-glycol structure and their 3 beta-epimers by proton and carbon-13 nuclear magnetic resonance spectroscopies are briefly discussed along with the mass spectrometric properties.

Among various unsaturated fatty acids which were examined in this experiment, trans-2-tridecenoic acid was found to be a potent inhibitor on gastric secretion in rats (i.p. or i.d.). Therefore, the effects of trans-2-tridecenoic acid on several experimental ulcerations in rats were examined. At the dose of 10 mg/kg, trans-2-tridecenoic acid significantly decreased the ulcer index in pylorus-ligated rats; aspirin-, phenylbutazone-, histamine- and stress-induced ulcerations were also significantly inhibited at the dose of 25 mg/kg. Finally, effects of trans-2-tridecenoic acid on hexosamine and sialic acid contents in the gastric mucous were examined. In intact or phenylbutazone-induced ulcerated rats, trans-2-tridecenoic acid increased the sialic acid levels in the gastric mucous at the dose of 25 mg/kg. The decreased hexosamine content in the gastric mucous by phenylbutazone treatment was recovered by the administration of trans-2-tridecenoic acid.