Beminamycinic acid

Thiazolo[2,3-/][l,6]naphthyridin-4-ium hydroxide, anhydro-3,8-dicarboxy-6-hydroxy- — see Beminamycinic acid Thiazolonaphthyridinium salts desulfurization, 6, 687 Thiazolones mesoionic... 

Beminamycinic acid Thiazolonaphthyridinium salts desulfurization, 6, 687 Thiazolones mesoionic... 

Carboxy-6-hydroxythiazolo[2,3-/ [ 1,6]-naphthyridin-4-ium-3-carboxylate (152) (beminamycinic acid) underwent exhaustive methylation to afford methyl 8-methoxy-6-(l-methoxycarbonyl-2-methylthiovinyl)-5-oxo-5,6-dihydro-1,6-naphthyridine-2-carboxylate (153) (Mel, Ag20 low yield)293 or hydrogenolysis to furnish a separable mixture of 6-(l-carboxylatoethyl)-8-hydroxy-l,2,3,4-tetrahydro-l,6-naphthyridin-6-ium-2-carboxylic acid (154) and 8-hydroxy-1,2,3,4-tetrahydro-l,6-naphthyridine-2-carboxylic acid (155) (Raney Ni, NaOH, H20 unstated yields).274... 

In pyridines, the ortho lithiation of 2-substituted secondary and tertiary amides and sulfonamides has been reported. All three afford regioselective metalation at the 3-position, as illustrated by Kelly s synthesis of beminamycinic acid (23 Scheme 30). A recent development is the use of catalytic amounts of diisopropylamine for the ortho metalation of 2-methoxypyridine. ... 

Beminamycinic acid, a degradation product of the antibiotic berninamycin, has been shown to have structure (207) by A -ray analysis. ... 

Lau RCM, Rinehart KL Biosynthesis of beminamycin Incorporation of C labeled amino acids. ] Am Chem Soc 1995 117 7606-7610. 

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