and Andrew J. P. White

New antifeedant neo-clerodane triol. Semisynthesis and antifeedant activity of neo-clerodane diterpenoids

Abstract Methyl 2α,3β,4β-trihydroxy-neo-clerodan-15-oate was isolated from the acid fraction of Cistus populifolius and its structure determined by semisynthesis and confirmed by X-ray diffraction. Three other triols (2, 3 and 4) and an intermediate diol (5) were also synthesized as potential antifeedants. The functional groups and stereochemistry for antifeedancy are discussed.

Synthesis and characterisation of substituted diphenylamines—charge-transfer, donor–acceptor systems localised at water–oil interfaces

A range of charge-transfer, donor–acceptor systems have been synthesised and subjected to in-depth crystallographic, spectroscopic and interfacial studies. The pyridine- or phenyl-substituted (N,N-diphenyl)amino derivatives contain an identical donor unit, NR3, and acceptor species with varying acceptor strength, with three compounds (3, 6 and 9) being characterised by X-ray structural analysis. Two of the compounds, the methyl 6 and octyl 8 derivatives, show interfacial localisationviafluorescence confocal microscopy and illustrate their potential as light-driven optical machines.

Total Synthesis of Antifungal Natural Products

There is great concern amongst the medical profession regarding fungal disease, with dermatophyte infections such as tinea pedis and candidiasis, although usually not fatal, being prevalent throughout the world (Kwon-Chung and Bennett 1992). Pathogens such as Candida albicans, Cryptococcus neoformans, Pneumocystis carinii and Aspergillus fumi-gatus have a far more gruesome reputation and are the cause of considerable mortality in immunocompromised patients. Populations at risk from these opportunistic fungal infections include AIDS patients, recipients of cancer chemotherapy and persons with genetically impaired or drug-suppressed immune function. Fungal pneumonia, induced by Pneumocystis carinii, is the cause of death in the majority of AIDS patients. Invasive pulmonary aspergillosis is the scourge of patients subject to cancer chemotherapeutic regimes. Current treatments for serious systemic fungal infection are deficient, and the gold standard amphotericin is acutely toxic (Kwon-Chung and Bennett 1992). There are now resistance problems with azole fungistatic agents such as fluconazole. Novel therapies are therefore needed for serious fungal disease and for the management of the multitude of topical fungal infections. In consequence, several pharmaceutical companies worldwide are seeking to develop superior fungicidal agents. Due to evolutionary pressures of microbial antagonism, fermentation broths are rich sources of novel anti-infective agents.