scholarly journals Microbiological degradation of bile acids. Metabolites formed from 3-(3a α-hexahydro-7a β-methyl-1,5-dioxoindan-4 α-yl) propionic acid by Streptomyces rubescens

1977 ◽  
Vol 164 (3) ◽  
pp. 715-726 ◽  
Author(s):  
S Hashimoto ◽  
S Hayakawa

1. The metabolism of 3-(3a alpha-hexahydro-7a beta-methyl-1,5-dioxoindan-4 alpha-yl)propionic acid (III), which is a possible precursor of 2,3,4,6,6a beta, 7,8,9,9a alpha,9b beta-decahydro-6a beta-methyl-1H-cyclopenta[f]quinoline-3,7-dione (II) formed from cholic acid (I) by streptomyces rubescens, was investigated by using the same organism. 2. This organism effected amide bond formation, reduction of the carbonyl groups, trans alpha beta-desaturation and R-oriented beta-hydroxylation of the propionic acid side chain and skeleton cleavage, and the following metabolites were isolated as these forms or their derivatives: compound (II), 1,2,3,4 a beta,-5,6,6a beta,7,8,9a alpha,9b beta-dodecahydro-6a beta -methylcyclopental[f][1]benzopyran-3,7-dione (IVa), (1R)-1,2,3,4a beta,5,6,6a beta,7,8,9.9a alpha,9b beta-dodecahydro-1-hydroxy-6a beta-methylcyclopenta[f][1]benzopyran-3,7-dione (IVb), (E)-3-(3aalpha-hexahydro-5 alpha-hydroxy-7a beta-methyl-l-oxo-indan-4 alpha-yl)prop-2-enoic acid (V), (+)-(5R)-5-methyl-4-oxo-octane-1,8-dioic acid (VI), 3-(4-hydroxy-5-methyl-2-oxo-2H-pyran-6-yl)propionic acid (VII) and 3-(3a alpha-hexahydro-1 beta-hydroxy-7a beta-methyl-5-oxoindan-4 alpha-yl)propionic acid (VIII). The metabolites (IVb), (V), (VI) and (VII) were new compounds, and their structures were established by chemical synthesis. 3. The question of whether these metabolites are true degradative intermediates is discussed, and a degradative pathway of compound (III) to the possible precursor of compound (VII), 7-carboxy-4-methyl-3,5-dioxoheptanoyl-CoA (IX), is tentatively proposed. The further degradation of compound (IX) to small fragments is also considered.

1976 ◽  
Vol 160 (3) ◽  
pp. 745-755 ◽  
Author(s):  
S Hayakawa ◽  
S Hashimoto ◽  
T Onaka

The metabolism of cholic acid (I) by Streptomyces rubescens was investigated. This organism effected ring A cleavage, side-chain shortening and amide bond formation and gave the following metabolites: (4R)-4-[4α-(2-carboxyethyl)-3aα-hexahydro-7aβ-methyl-5-oxoindan-1 β-yl]valeric acid (IIa) and its mono-amide (valeramide) (IIb); and 2,3,4,6, 6aβ,7,8,9,9aα,9bβ-decahydro-6aβ-methyl-1H-cyclopenta[f]quinoline-3,7-dione(IIIe)and its homologues with the β-oriented side chains, valeric acid, valeramide, butanone and propionic acid, in the place of the oxo group at C-7, i.e.compounds (IIIa), (IIIb), (IIIc) and (IIId) respectively. All the nitrogenous metabolites were new compounds, and their structures were established by partial synthesis except for the metabolite (IIIc). The mechanism of formation of these metabolites is considered. A degradative pathway of cholic acid (I) into the metabolites is also tentatively proposed.


2016 ◽  
Vol 0 (0) ◽  
Author(s):  
Julia Nowak-Jary

AbstractThe use of catalysts in the activation of carboxyl groups towards nucleophilic attack and the protection of other functional groups by suitable protecting groups are standard and necessary procedures in amide bond formation. In contrast to the usual methods, various new compounds, amides of APTES ((3-aminopropyl)triethoxysilane, 3-triethoxysilylpropylamine) and carboxyphenylboronic acids, as well as the amides of aniline and carboxyphenylboronic acids, were obtained in good yields by a one-step synthesis under mild conditions without using any coupling reagents or additional catalysts.


1986 ◽  
Vol 51 (17) ◽  
pp. 3320-3324 ◽  
Author(s):  
D. S. Kemp ◽  
Nicholas G. Galakatos ◽  
Stanley Dranginis ◽  
Christopher Ashton ◽  
Nader Fotouhi ◽  
...  

2018 ◽  
Vol 16 (1) ◽  
pp. 30-33
Author(s):  
Ashish Kumar ◽  
Yahya E. Jad ◽  
Ayman El-Faham ◽  
Beatriz G. de la Torre ◽  
Fernando Albericio

A new phosphonium based coupling reagent DEPO-B has been synthesized from 5- (hydroxyimino)-1,3-dimethylpyrimidine-2,4,6 (1H,3H,5H)-trione (Oxyma B) and diethyl chlorophosphate in presence of base. It is a solid material and the hydrolytic stability and solubility was evaluated for confirming its capability for usage in automated peptide synthesizer.


2014 ◽  
Vol 11 (4) ◽  
pp. 592-604 ◽  
Author(s):  
Natalia Lukasik ◽  
Ewa Wagner-Wysiecka

2017 ◽  
Vol 15 (30) ◽  
pp. 6367-6374 ◽  
Author(s):  
Song-Lin Zhang ◽  
Hai-Xing Wan ◽  
Zhu-Qin Deng

A detailed computational study is presented on the reaction mechanism of ynamide-mediated condensation of carboxylic acids with amines to produce amides, which elucidates the reactivity pattern of the coupling reagent ynamide and discloses crucial bifunctional catalytic effects of the carboxylic acid substrate during aminolysis.


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