摘要:
To enable solid-state NMR investigations of the rhodopsin chromophore and its photointermediates, a series of 11Z-retinal isotopomers have been synthesised containing pairs of adjacent C-13 labels at C9/C10, C10/C11 or C11/C12, respectively. The C9 labelled carbon atom was introduced through the Heck reaction of a C-13-labelled Weinreb acrylamide derivative, and the label at the C12 position derived from a C-13-containing ethoxy Bestmann-Ohira reagent. The C-13 labels at C10 and C11 were introduced through the reaction of beta-ionone with labelled triethyl phosphonoacetate. (C) 2011 Elsevier Ltd. All rights reserved.