Etude de structures peptidiques à l'aide de phénylisothiocyanate VII [1] Sur la réaction de quelques acides aminés et de queiques thiols avec le phénylisothiocyanate

A Facile Regioselective 1,3-Dipolar Cycloaddition Reaction for the Synthesis of Dispiro[Indole-3,2-Pyrrolidine-3′,5″-[1,3]Thiazolidine] Derivatives

The 1,3-dipolar cycloaddition reaction of azomethine ylides generated in situ from isatin and sarcosine with 5-arylmethylene-3-phenyl-2-thioxothiazolidin-4-one in refluxing toluene produced the 2″-thioxodispiro[indole-3,2′-pyrrolidine-3′,5″-[1,3]thiazolidine]-2,4″-dione derivatives in good yields (80–88%). The structures were assigned by 1H NMR, IR, elementary analysis and single crystal X-ray diffraction analysis through which the cycloaddition reaction was found to be highly regio- and stereo-selective.

Substituted hippurates and hippurate analogs as substrates and inhibitors of peptidylglycine alpha-hydroxylating monooxygenase (PHM)

Peptidyl alpha-hydroxylating monooxygenase (PHM) functions in vivo towards the biosynthesis of alpha-amidated peptide hormones in mammals and insects. PHM is a potential target for the development of inhibitors as drugs for the treatment of human disease and as insecticides for the management of insect pests. We show here that relatively simple ground state analogs of the PHM substrate hippuric acid (C(6)H(5)-CO-NH-CH(2)-COOH) inhibit the enzyme with K(i) values as low as 0.5microM. Substitution of sulfur atom(s) into the hippuric acid analog increases the affinity of PHM for the inhibitor. Replacement of the acetylglycine moiety, -CO-NH-CH(2)-COOH with an S-(thioacetyl)thioglycolic acid moiety, -CS-S-CH(2)-COOH, yields compounds with the highest PHM affinity. Both S-(2-phenylthioacetyl)thioglycolate and S-(4-ethylthiobenzoyl)thioglycolic acid inhibit the proliferation of cultured human prostate cancer cells at concentrations >100-fold excess of their respective K(i) values. Comparison of K(i) values between mammalian PHM and insect PHM shows differences in potency suggesting that a PHM-based insecticide with limited human toxicity can be developed.