Isolation and structure elucidation of a novel griseorhodin.

Absolute configurations of griseorhodins A and C

“…2–5 Griseorhodins A and C have been described with antimicrobial activity against B. subtilis , S. aureus , P. notatum and others; and with cytotoxic activity against cells derived from human carcinoma of nasopharynx (KB). 6,7 Griseorhodin A also inhibits human leukocyte elastase at micromolar concentrations. 8 Both griseorhodins A and C inhibit the moloney murine leukemia virus reverse transcriptase (M-MLV RT) with IC 50 values of 7.38 and 9.38 μM, respectively.…”

Isolation of Structure of Dideoxy-griseorhodin C Produced by a Streptomyces sp.

“…76, that produced two red pigments. We isolated the two compounds from its culture broth, one of them was identical with griseorhodin C (1)1-7) and the other, which we named dideoxygriseorhodin (2), turned out to be a new griseorhodin compound. This paper describes the production, isolation and elucidation of the structure of 2.…”

“…Comparison of the IH-NMR spectrum of dideoxygriseorhodin C (2) 21. 30 and the S-C carbon signal at be 23.24 were negative.…”

Synthesis of the carbon skeleton of the griseorhodins

“…5,6,8,9 Notably, 8-methoxygriseorhodin C (4) exhibits potent activity against strains of MRSA (methicillin resistant Staphylococcus aureus, MIC¼0.78 mg/ mL). 6 These natural products also exhibit cytotoxic activity against KB-nasopharynx cells and HLE (human leukocyte elastase).…”

“…6 These natural products also exhibit cytotoxic activity against KB-nasopharynx cells and HLE (human leukocyte elastase). 5,9 In addition to their potent antimicrobial and cytotoxic properties, griseorhodins A (1) (IC 50 12.2 mM) and C (2) (IC 50 5.87 mM) also inhibit human telomerase. 10 Telomerase is a unique ribonucleoprotein that maintains the ends of chromosomes, through the synthesis of telomeres.…”