Synthesis of Zwitter-Ionic Conjugate of Nido -Carborane with Cholesterol

9-HC≡CCH Me N- -7,8-C B H , a previously described carboranyl terminal alkyne, was used for the copper(I)-catalyzed azide-alkyne cycloaddition with azido-3β-cholesterol to form a novel zwitter-ionic conjugate of -carborane with cholesterol, bearing a 1,2,3-triazol fragment. The conjugate of -carborane with cholesterol, containing a charge-compensated group in the linker, can be used as a precursor for the preparation of liposomes for BNCT (Boron Neutron Capture Therapy). The solid-state molecular structure of a -carborane derivative with the 9-Me N(CH ) Me N- -7,8-C B H terminal dimethylamino group was determined by single-crystal X-ray diffraction.