Ronald Mierzwa

Wiedendiol-A and -B, cholesteryl ester transfer protein inhibitors from the marine sponge Xestospongia wiedenmayeri

Abstract Wiedendiol-A and -B, novel sesquiterpene-hydroquinones which inhibit cholesteryl ester transfer protein (CETP), have been isolated from the marine sponge Xestospongia wiedenmayeri. Additional related marine natural products were also evaluated for CETP inhibition. Compounds that inhibit the activity of CETP may find utility as antiatherosclerosis therapy.

Structure of Sch 68631: A new hepatitis C virus proteinase inhibitor from Streptomyces sp.

Abstract A novel hepatitis C virus (HCV) proteinase inhibitor, Sch 68631 ( 1 ), was isolated from the fermentation culture broth of Streptomyces sp. The structure of 1 was elucidated by analyses of spectroscopic data and shown to be a new member of the phenanthrenequinone family of compounds.

Two novel diketopiperazines isolated from the fungus Tolypocladium sp.

Abstract Diketopiperazines, Sch 54794 and Sch 54796, have been isolated from a fungal fermentation. The structures of these compounds have been established based on spectroscopic data analysis. Sch 54794 exhibited inhibitory activity in the platelet activating factor (PAF) assay.

A new sterol sulfate, Sch 572423, from a marine sponge, Topsentia sp.

Bioassay-guided fractionation of an active fraction from a marine sponge Topsentia sp. in our marine fraction library (MFL) led to the isolation and identification of halistanol sulfate (1) and a new sterol sulfate Sch 572423 (2). Compounds 1 and 2 were identified as P2Y(12) inhibitors with IC(50) of 0.48 and 2.2 microM, respectively. The general method of purification for the MFL library and the structure elucidation of compound 2 are described.

A new fungal metabolite, Sch 202596, with inhibitory activity in the galanin receptor GALR1 assay

Abstract A novel spirocoumaranone, Sch 202596 ( 1 ), was isolated from the fermentation broth of Aspergillus sp. The isolation, structure elucidation and stereochemistry of 1 are described.

Isolation and structure of SCH 351633 : A novel hepatitis C virus (HCV) NS3 protease inhibitor from the fungus Penicillium griseofulvum

A new hepatitis C virus (HCV) protease inhibitor designated as Sch 351633 (1) was isolated from the fungus, Penicillium griseofulvum. Structure elucidation of 1 was accomplished by analysis of spectroscopic data, which determined compound 1 to be a bicyclic hemiketal lactone. Compound 1 exhibited inhibitory activity in the HCV protease assay with an IC50 value of 3.8 microg/mL.

Usnic acid amide, a phytotoxin and antifungal agent from Cercosporidium henningsii

Abstract Usnic acid amide, a phytotoxin related to (−)-usnic acid and (−)-cercosporamide, has been isolated from the cassava fungal pathogen Cercosporidium henningsii . Usnic acid amide also shows moderate antifungal activity and inhibiton of protein kinase C.

Sch 65676: A novel fungal metabolite with the inhibitory activity against the cytomegalovirus protease

A new secondary metabolite, Sch 65676 (1), was isolated from the fermentation broth of a fungal culture. The structure of 1 was elucidated based on comprehensive NMR studies including COSY, NOE and HMBC experiments. Compound 1 displays inhibitory activity against the cytomegalovirus (CMV) protease.

Sch 213766, A Novel Chemokine Receptor CCR-5 Inhibitor from Chaetomium globosum

A novel fungal secondary metabolite, Sch 213766 was isolated from the fungal fermentation broth of Chaetomium globosum as the chemokine receptor CCR-5 inhibitor and shown to be the methyl ester of the previously described tetramic acid Sch 210972 on the basis of UV, MS and NMR spectral data analyses. Sch213766 exhibited an IC50 value of 8.6 μM in the CCR-5 receptor in vitro binding assay.

A new potent antifungal agent from Actinoplanes sp

Abstract A novel antifungal agent, Sch 56036 ( 1 ), was isolated from the fermentation culture broth of an Actinoplanes sp. Structure elucidation of 1 was accomplished by the analysis of spectroscopic data. Compound 1 was identified as a new polycyclic xanthone. Biological evaluation of 1 indicated that the compound possesses broad spectrum antifungal activity against various yeasts and dermatophytes with geometric mean MIC values ranging from 0.017∼0.031 μg/mL, respectively.