Sulfoquinovosylglyceryl ether, a new group of ether lipids from lake ball-forming green alga Aegagropilopsis moravica (family Pithophoraceae).

Ether lipids are a minor group of glycerolipids but widespread in nature, playing a vital function as membrane lipids, signalling molecules, or buoyant material. We have discovered sulfoquinovosylchimyl alcohol (1), a sulfonate-substituted glyceroglycolipid, from a lake ball-forming green alga Aegagropilopsis moravica (family Pithophoraceae), with the guidance of antimicrobial activity. The structure of 1, including absolute configurations of all sterogenic centers, was established by extensive NMR analysis, chemical degradation studies, and finally by total synthesis.

Two new 2-alkylquinolones, inhibitory to the fish skin ulcer pathogen , produced by a rhizobacterium of the genus sp.

Exploration of rhizobacteria of the genus as an under-tapped resource of bioactive molecules resulted in the isolation of two new antimicrobial 2-alkyl-4-quinolones. ()-2-(Hept-2-en-1-yl)quinolin-4(1)-one () and ()-2-(non-2-en-1-yl)quinolin-4(1)-one () were isolated from the culture broth of strain MBAF1239 together with four known alkylquinolones ( and -), pyrrolnitrin (), and BN-227 (). The structures of and were unambiguously characterized using NMR spectroscopy and mass spectrometry.