No abstract

CO2 capture at low concentration by catalysts is potentially useful for developing photocatalytic and electrocatalytic CO2 reduction systems.

Here we examined the use of continuous flow conditions for the final assembly of eribulin mesylate aimed to avoid cryogenic condition. The diisobutylaluminum hydride reduction of ester 2 to aldehyde 3 and nbutyllithium-mediated coupling of aldehyde 3 and sulfone fragment 4 to produce sulfone-diol 5 were investigated. Under optimized continuous flow conditions, both reactions could be run at temperatures higher than those used under batch conditions. For the diisobutylaluminum hydride reduction of ester 2 to aldehyde 3, under optimized continuous flow conditions at −50 °C, aldehyde 3 was afforded with better HPLC area ratio than it was under batch conditions at −70 °C. Furthermore, continuous operation for 87 min afforded the same quality of 3 as was produced with a short-time operation (yield, 96.5%). For the n-butyllithium-mediated coupling of 3 and 4, under optimized continuous flow conditions at 10 °C, 5 was afforded with a better conversion rate than it was under batch conditions at −70 °C.

No abstract

Total syntheses of cyclo (-Gly-L-Lys-L-Val-(i?)-3-aminododecanoyl-); LV9nA and its diastereomer cyclo (-Gly-L-Lys-L-Val-(S)-3-aminododecanoyl-); LV9nB, congeners of rhodopeptin B5 on /3-amino acid moiety, were achieved. The /3-amino acid moiety was prepared as a racemate by the thermal Michael addition of an amine to a,/3-unsaturated ester. The racemic fiamino acids were converted to their L-Valylamide derivatives and the obtained diastereomers were separated.