Glucosamine 유도체의 입체선택적 합성(III): 벤질화 반응에서 치환체의 영향

Abstract

Nine diferent kinds of N-benzylamino-α-D-glucosamine derivatives 6 in which anomeric carbon at C-1 of glucosamine wassubstituted to acetoxy moiety and the intermediate 2-benzylidene-α-D-glucosamine 5 were separated. 2-Benzylidene-β-D-glucosamine 4 which had another stereochemistry of anomeric carbon was obtained in high yield from the similar reaction ofanomeric mixture of glucosamine 1 with phenylaldehyde derivatives. 2-Benzylidene-α-D-glucosamine 5 was acquired from thereaction of α-D-glucosamine 3 with phenylaldehyde, and then with sodium cyanoborohydride, and the highest yield of 5 wasobserved as the reaction time of 1 hour. N-benzylamino-α-D-glucosamine was obtained by the continuous reaction of 24 hoursby sodium cyanoborohydride. The products were separated and purified by medium pressure liquid chromatography(MPLC) andthe new 6 showed relatively low melting point less than 10oC or oily liquid. The structures and the physical properties ofsynthesized new substances were elucidated by their 1H NMR spectroscopy. The H-1 proton of N-benzylamino-α-D-glucosamine showed a singlet at 6.2 ppm with J value of 3-4 Hz, and methylene proton in benzyl group showed a quartet of ABpattern with J value of 13 Hz.