naphthoquinones and anhydrofusarubin

Natural products display a large structural variation and different uses within a broad spectrum of industries. In this study, we investigate the influence of carbohydrates and nitrogen sources on the production and selectivity of production of four different polyketides produced by

Topics: Culture Media; Fusarium; Isoquinolines; Naphthoquinones; Nitrogen; Polyketides; Sucrose

Topics: Animals; Antineoplastic Agents; Apoptosis; Bone Marrow Cells; Cell Line, Tumor; Cell Proliferation; Cladosporium; Female; Humans; Mice, Inbred C57BL; Naphthoquinones

Five new 3-O-alkyl-4a,10a-dihydrofusarubins (2-6) were isolated from the culture filtrate of a strain of Fusarium sp. (Mj-2), together with the known metabolite, anhydrofusarubin (1). The structures of the new metabolites were elucidated by spectroscopic analyses to be 3-O-butyl, 3-O-3'-methylbutyl, 3-O-2'-methylbutyl and 3-O-2'-phenylethyl-4a,10a-dihydrofusarubin A, and an isomer of 3-O-2'-phenylethyl-4a,10a-dihydrofusarubin A. Their antifungal and antibacterial activities were evaluated together with a 3-O-methyl derivative (7) prepared from 3-O-butyl-4a,10a-dihydrofusarubin A (2), indicating that the size of the O-substituent at C-3 in the 4a,10a-dihydrofusarubins negatively affected the metabolites' antimicrobial activity.

Topics: Anti-Bacterial Agents; Antifungal Agents; Culture Media; Fermentation; Fusarium; Magnetic Resonance Spectroscopy; Naphthols; Naphthoquinones; Structure-Activity Relationship

The synthesis of two closely related pyranonaphthoquinones, dehydroherbarin and anhydrofusarubin, is described. The construction of the naphthalene nuclei was achieved using the Stobbe condensation reaction using 2,4-dimethoxybenzaldehyde and 2,4,5-trimethoxybenzaldehyde as their respective starting materials. Two key steps en route include a PIFA-mediated addition of a methoxy substituent onto the naphthalene skeleton and a Wacker oxidation reaction to construct the benzo[g]isochromene nucleus. Two interesting oxidation reactions of the intermediate isochromene enol ether of 7,9-dimethoxy-3-methyl-1H-benzo[g]isochromene-5-ol were observed. Treatment of the substrate with salcomine resulted in the formation of (3-formyl-4-hydroxy-6,8-dimethoxynaphthalene-2-yl)methyl acetate, while treatment of the same substrate with CAN resulted in the formation of racemic (3R,4R)-3-hydroxy-7,9-dimethoxy-3-methyl-5,10-dioxo-3,4,5,10-tetrahydro-1H-benzo[g]isochromen-4-yl nitrate.

Topics: Cerium; Crystallography, X-Ray; Models, Molecular; Molecular Structure; Naphthoquinones; Organometallic Compounds; Oxidation-Reduction