%0 Journal Article %T Synthetic Studies on Erythromycin Derivatives: Reactivity of the C12-21 Alkene %A Wei-Min Chen %J Molecules %D 2006 %I MDPI AG %R 10.3390/11010121 %X The reactivity of the C12-21 alkene of some erythromycin A derivatives was studied. This double bond was easily oxidized to the corresponding epoxide with excellent stereoselectivity. A single crystal X-ray structure showed that the epoxide moiety was on the same side as the acetonide. When an erythromycin derivative containing a C12-21 alkene was treated with diazomethane a [3+2] cycloaddition affording a pyrazoline occurred. In the case of 6-O-allylated erythromycin derivatives the C12-21 alkene was selectively epoxidized in the presence of the 6-O-allyl moiety. These results show that the C12-21 alkene is an active reaction site, which can be used for useful further modification of erythromycin derivatives. %K Erythromycin %K alkene %K epoxidation %K cycloaddition %K pyrazoline. %U http://www.mdpi.com/1420-3049/11/1/121