Trimethylsilyl retinoids

Some trimethylgermyl and trimethylsilyl derivatives of retinobenzoic acids show high retinoidal activity in human promyelocytic leukaemia cells HL-60135. 

Retinoids. Several routes have been described for the preparation of retinal and its derivatives. Two papers ° on the use of trimethylsilyl and triphenylsilyl protecting groups describe the preparation of the Ce intermediate -3-methyl-pent-2-en-4-yn-l-ol triphenylsilyl ether (100), and the four- or five-step synthesis of IIZ-retinal from this and the C14 aldehyde (101). A method for base-catalysed trans elimination of PhSOaH from the sulphone (102) affords retinyl acetate (103) in 86% yield. 

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