Synthesis of Analogues of Pramanicin for Bioactivity Analysis

Abstract

<p> Pramanicin (1) is a natural product that was first isolated as an anti-fungal agent: it possesses bioactivity against both the acapsular and capsular forms of Cryptococcus neoformans. 1 was found to act on smooth muscle in an endotheliumdependent manner. Further, studies of Ca2+ release from the endoplasmic reticulum of endothelial cells were consistent with an influence on the endothelial nitric oxide synthase (eNOS) pathway. Recently, we showed that 1 activates caspases 3 and 9. In order to determine which functional groups in 1 are required for this activity, several analogues were prepared (2~7). These included 2 and 3 prepared through fermentation and modification of 1, as well as 4-7 which were prepared by chemical synthesis. A test of bioactivity for 1-7 indicates that all compounds are active. The small differences in activity are discussed. </p>