Novel spirodihydrobenzofuranlactams as antagonists of endothelin and as inhibitors of HIV-1 protease produced by Stachybotrys sp. II. Structure determination.

Six novel spirodihydrobenzofuranlactams I ~ VI (1 ~ 6) (Fig. 1) have been identified in extracts of two different Stachybotrys species as antagonists of endothelin and as inhibitors of HIV-1 protease. In a recently published paper1} we described the fermentation, isolation and biological properties of these secondary metabolites 1 ~6. Besides this novel class of the spirodihydrobenzofurans including the lactams 1 ~4, 6 and the imide 5 the known spirodihydrobenzofuranalcohol L-67 1 7762) was isolated. This inositol-phosphate phosphatase and HIV1 protease