Indolmycenic acid

The first, and one of the most straightforward, syntheses of racemic 69 was that of Schach von Wittenau and Els ° after they had determined the stmcmre. Friedel-Crafts alkylation of indole with ethyl 2,3-epoxybutyrate gave the a-indolmycenic acid ester 119a. Cyclization of 119a with Af,//-dimethylguanidine yielded both 69 and isoindolmycin 120 (Scheme 6.32). In this case, facile epimerization of H-5 had occurred under the basic cyclization conditions. 

INDOLMYCIN (20) is formed from pyruvate, and two enzymes active in initial stages of Its biosynthesis have been studied. They are a transaminase and aC-methyltransferase. The hypothetical route to indolmycin is by indole pyruvate, 3-methyl-indolepyruvate, indolmycenic acid (reduced alpha oxo group) and finally indolmycin which probably takes its amidine group from an arginine molecule 79. The closely related [pyrrolo (1,4) benzodiazepines] 80>81,82 antitumor antibiotics, anthramycin, tomaymycin and sibiromycin are formed from tryptophan (via the kynurenine pathway ), tyrosine and methionine-derived methyl groups 80.si.sz. 

Indolmycin.—Of the four optical isomers of indolmycenic acid which might serve as precursors for indolmycin (121), only the naturally occurring isomer (120), with the same absolute stereochemistry as indolmycin, is significantly incorporated in Streptomyces griseus. ... 

Scheme VII. Degradation of indolmycin and indolmycenic acid to recover the chiral methyl groups as acetic acid.

Indolmycin.—It has been shown" that indolmycin (39 corrected stereochemistry) is derived from its co-metabolite in Streptomyces griseus, indolmycenic acid (45 corrected stereochemistry). 

Indolmycenic acid, Y27 Indolmycin, Y27 Ingenol, T39 Inositol, A16 tnosose, A16 Intermedol, T19 Inumakilactone, T38 lonones, T54 Ipecacuanha alkaloids, K2 Ipecoside, K2 Ipsdienol, All ... 

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