Microbial transformations of natural antitumor agents: use of solubilizing agents to improve yields of hydroxylated ellipticines

Microbial transformations of natural antitumor agents: conversion of lapachol to dehydro-alpha-lapachone by Curvularia lunata.

Microbial transformation of lapachol, a naturally occurring naphthoquinone, was carried out by Curvularia lunata (NRRL 2178). The fungus brings about oxidative cyclization of the substrate to dehydro-alpha-lapachone, which was isolated and characterized by nuclear magnetic resonance and mass spectral analyses; its structure was verified by chemical synthesis. The metabolite is a naturally occur...

Microbial Transformations of Natural Antitumor Agents: Products of Rotenone and Dihydrorotenone Transformation by Cunninghamella blakesleeana.

Various species of Absidia, Aspergillus, Cunninghamella, Trichothecium, Penicillium, and Phanerochaete were found to transform rotenone to one or more metabolites. Two biotransformation products were isolated from a preparative-scale incubation of rotenone with Cunninghamella blakesleeana and identified as 1',2'-dihydro-1',2'-dihydroxyrotenone and 3'-hydroxyrotenone (amorphigenin). The catalyti...

Use of Volsurf approach for pharmacokinetic optimization of β-carboline derivatives as antitumor agents

The β-carboline derivatives are a large group of naturally-occurring and synthetic alkaloids which have awide spectrum of biological and pharmaceutical properties. The newly developed procedure called VolSurfhas been used to explore a significant correlation between the 3D molecular interaction fields (MIF) andphysicochemical and pharmacokinetic properties of a set of 30 β-carboline compounds a...

Natural Products as Sources of Antitumor Agents

The Effect of Temperature, pH, and Different Solubilizing Agents on Stability of Taxol

       Inabilities to attain adequate aqueous solubility and stability have made the preparation of a clinically suitable formulation of taxol difficult. Addition of nicotinamide (ND), 2-hydroxypropyl- b-cyclodextrin (HPßCD), polyethylene glycol, (PEG), bile salts (BS, 50:50 sodium cholate: deoxycholate...