The isolation, identification, and bioassay of the antifungal metabolites produced by Monocillium nordinii

Abstract

The metabolites produced when Monocillium nordinii (Bourchier) W. Gams, a destructive mycoparasite of pine stem rusts, is grown in liquid culture have been separated and identified. The metabolites include the known compound monorden (1) and five new substances, monocillin I (2), monocillin II (4), monocillin III (3), monocillin IV (5), and monocillin V (6). Structural assignments and chemical correlations of the five new compounds are reported and the absolute configuration of monorden is assigned. The antifungal spectra of the three major metabolites are reported. Monorden and monocillin I show pronounced activity against a wide variety of fungi, including Ceratocystis ulmi, the cause of Dutch elm disease. Extraction of the mycelium yielded averufin (13), along with a pigment C18H12O6, as yet unidentified.

Targeting of the protein chaperone, HSP90, by the transformation suppressing agent, radicicol

“…With this goal in mind, a biotinylated derivative of radicicol was synthesized. The structure of radicicol (shown in Figure 1b) contains an epoxide residue that is critical for its antifungal properties (Ayer et al, 1980) and may play a role in its biological activity as a tyrosine kinase inhibitor (Kwon et al, 1992a). In addition, radicicol, like many other tyrosine kinase inhibitors, possesses phenolic ring structures that may be necessary for its function.…”

Stereoselective total synthesis of the antiplasmodial resorcylic acid lactone paecilomycin F

“…R f 0. 8 (12). To a solution of compound 17 (700 mg, 2.78 mmol) in CH 2 Cl 2 (20 mL) was added a solution of trifluoromethanesulfonic anhydride (0.5 mL, 3.05 mmol) at -78 °C over 5 min, and the resulting solution was stirred for 30 min.…”

“…The resorcylic acid lactones with unique structural architecture are also found to exhibit potent biological activities ranging from antimalarial, 6 antiviral, antiparasitic, 7 antifungal, 8 cytotoxic, 9 estrogenic 10 to nematocidal 11 activities. Over the years, these molecules have emerged as common targets for total synthesis and have led medicinal chemists to design analog programmes leading to a number of clinical trials.…”

Applications of Chiral Three-membered Rings for Total Synthesis: A Review

“…Moreover, [3+2] asymmetric cycloaddition reactions of epoxides have also recently emerged as valuable tools to obtain chiral dihydro-or tetrahydrofuran derivatives, important core structures present in natural products [57]. Besides the relevance of chiral epoxides in synthesis, a great number of natural products and bioactive compounds exhibit the epoxide subunit in their structure as exemplified by sex pheromone for gypsy moth (+)-disparlure [58], antibiotic agent monocillin I [59], potent oral hypoglycemic and antiketogenic agent in mammals (R)-methyl palmoxirate [60], and anticancer agents ovalicin, fumagillin and ephothilones A and B [61]. The epoxidation of alkenes is undoubtedly the most investigated and convenient approach to obtain epoxides [62].…”