C32 and C34 hopanoids in recent sediments of European lakes: novel intermediates in the early diagenesis of biohopanoids

A study of hopanoids in the sediments of five European lakes has identified bacteriohopane-32,33,34,35-tetrol, 35-methoxybacteriohopane-32,33,34-triol and two new hopanoids with shorter side chains: 35-norbacteriohopane-32,33,34-triol and 33,34,35-trinorbacteriohopane-31,32-diol. Their structures have been revealed by mass spectrometry. Polyfunctionalised hopanoids with shortened side-chains are not often reported in sediments, mainly due to the analytical procedures used. Their systematic investigation could shed further light upon the early diagenesis of biohopanoids.