naphthomycin and 3-amino-5-hydroxybenzoic-acid

Covering: 1957 to 2011. 3-Amino-5-hydroxy benzoic acid (3,5-AHBA) is a precursor for a large group of natural products, including the family of naphthalenic and benzenic ansamycins, the unique saliniketals, and the family of mitomycins. This review covers the biosynthesis of AHBA-derived natural products from a molecular genetics, chemical, and biochemical perspectives, and 174 references are cited.

Topics: Actinomycetales; Aminobenzoates; Biological Products; Biosynthetic Pathways; Bridged Bicyclo Compounds, Heterocyclic; Hydroxybenzoates; Maytansine; Mitomycin; Molecular Structure; Naphthoquinones; Rifamycins

Fermentations of Streptomyces sp. E/784 produce low levels of the novel C-30 alkylthio-substituted ansamycin antibiotics naphthomycins J (9) and I (10), in addition to the more abundant C-30 hydroxylated analogues actamycin (1) and naphthomycin D (2) and C-30 chlorinated analogues naphthomycins H (3) and A (4). The addition of N-acetyl-L-cysteine to the fermentation medium substantially increases the production of the thionaphthomycins J and I at the expense of their chloro analogues H and A. Other thiols and thiol progenitors are similarly utilised, including N-acetyl-L-cysteine methyl ester which affords the known naphthomycin F (8) and its novel 2-demethyl homologue (7). The formation of thioansamycins from chloroansamycins and thiols in vivo is probably non-enzymic since similar conversions can be effected in vitro.

Topics: Acetylcysteine; Aminobenzoates; Anthraquinones; Anti-Bacterial Agents; Fermentation; Hydroxybenzoates; Lactams, Macrocyclic; Magnetic Resonance Spectroscopy; Molecular Structure; Naphthoquinones; Streptomyces