Application of the reaction of D-glucose with Meldrum's acid: Total synthesis of the styryl lactones (+)-goniofufurone and (+)-7-epi-goniofufurone

The syntheses of the styryl lactones (+)-goniofufurone (1) and (+)-7-epi-go niofufurone (2) from D-glucose are presented. The key steps are the formati on of the lactone moiety by reaction of the hemiacetals 15 and 16 with meld rum's acid (3) and the addition of phenylmagnesium bromide to the aldehydes 9 or 12. In the last case, we obtained the Lido and D-gluco configurated p roducts 13 and 14 in a 3:1 mixture. However, addition of ZnCl2 shifted the diastereomeric ratio towards the desired compound 14. (C) 1999 Elsevier Sci ence Ltd. All rights reserved.