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At least 397 records · Page 22Linked to original sources
PubMedDate not supplied

New 4-[omega-(diarylmethylamino)alkyl]- and 4-[omega-(diarylmethoxy)alkyl]-1-arylpiperazines as selective 5-HT1A/5-HT2A receptor ligands with differentiated in vivo activity.

Two series of novel 4-ethyl- or 4-propyl-1-arylpiperazines (5-12) with the 4,4'-disubstituted diphenylmethylamino (series a) or the diphenylmethoxy (series b) terminal fragment were synthesized and evaluated for their binding affinity at 5-HT1A and 5-HT2A receptors. The influence of the introduction of 4-methyl, 4-chloro or 4-fluoro substituents at both phenyl rings of that terminal moiety on in vitro and in vivo 5-HT1A receptor activity of those modified compounds was discussed. Compounds 5a, 6a, 9a-12a, 5b, 6b, 9b, 11b and 12b displayed high to fairly high affinity for 5-HT1A receptors (Ki = 2.4-72 nM). Compounds of both series showed low or very low 5-HT2A receptor affinity (Ki = 155-5400 nM). Amines 5a, 6a, 11a, and their ether analogs 5b, 6b and 11b, also possessed high or moderate alpha(1)-adrenoceptor affinity (K(i) = 6-104 nM). The functional activity of compounds 5a, 6a, 9a-12a, 5b, 8b, 9b, 11b and 12b was tested in vivo in the commonly used animal models. The majority of those ligands behaved like 5-HT1A receptor antagonists, their influence on the pre- and/or postsynaptic sites being diverse, though. They exhibited characteristics of partial agonists of postsynaptic 5-HT1A receptors (11a), of weak antagonists of pre- and postsynaptic sites (12a, 9b), of antagonists of presynaptic (5a) or of antagonists of postsynaptic 5-HT(1A) receptors (9a, 10a, 5b, 8b, 11b and 12b) while, 6a was devoid of functional activity at those receptors. The above findings indicate that introduction of 4-methyl, 4-chloro or 4-fluoro substituents to the diphenylmethyl part of the 1-(2-methoxyphenyl)piperazines tested in vivo may modify their 5-HT1A receptor functional activity.

Animals↗
PubMed1975

Production of 13beta-alkyl-3-methoxy-8,14-seco-1,3,5(10),9(11)-gonatetraen-14beta-ol-17-ones and 13beta-alkyl-3-methoxy-8,14-seco-1,3,5(10),9(11)-gonatetraen-17alpha-ol-14-ones by microbial enzymes.

For the purpose of producing hydroxy-keto-seco-steroids in which hydroxyl group is attached to a carbon atom having the R-configuration, numerous biochemically active microorganisms were tested without any success. The hydroxysteroid oxidoreductase enzymes of the investigated bacterial, yeast and fungal strains were suitable only for the production of 17beta-ol-14-one and 14alpha-ol-17-one derivatives. The required compounds were prepared by combinations of enzymatic reactions with chemical reduction. (i) By hydroxysteroid oxidoreductase of Saccharomyces uvarum and Saccharomyces drosophilarum, 17beta-ol-14-one and 14alpha-ol-17-one derivatives of 14,17-dione, respectively, were obtained. (ii) The above compounds were acetylated then reduced by sodium borohydride. (iii) 14beta,17beta-diol-17-acetate and 14alpha,17alpha-diol-14-acetate were dehydrogenated by dehydroxysteroid oxidoreductase of Nocardia sp. and Mycobacterum sp., respectively, in the presence of steroid esterase. The reaction mixture contained either 14beta-ol-17-one or 17alpha-ol-14-one derivatives, since oxidation by hydroxysteroid oxidoreductase was limited to the hydroxyl group attached to a carbon atom having the S-configuration.

17-Ketosteroids↗
PubMed1979

[Occurrence of alpha-alkyl-substituted malic acids, and beta-hydroxy-beta-alkyl-substituted dicarboxylic and tricarboxylic acid derivatives in normal urine (author's transl)].

Urine contains a number of alpha-hydroxy acids so far unknown to occur in biological liquids. Besides the already as urine constituent known methylmalic acid, also the ethyl, isopropyl and butyl derivatives of malic acid were found. Further metabolites in urine are a beta-propyl-substituted beta-hydrosyglutaric acid, a beta-hydroxy-beta-[methyl-carbomethoxy]-adipinic acid and two isomeric alpha-methylcitric acids.

Esters↗