D-mannose was acetylated,thiolated,deacetylated and benzoylated to provide a donor isopropyl 2,3,4,6-tetra-O-benzoyl-1-thio-α-D-mannopyranoside,and the donor was stereospecifically coupled with an acceptorL-menthol,subsequently deprotected to achieve L-menthyl α-D-mannopyranoside,the yield was obtained 32%.The products were characterized by melting point,optical rotation,NMR,MS etc.

建立了一种新的保护的二糖半乳吡喃糖基（α1→2）葡萄吡喃糖苷的合成方法。甲基-4,6-O-苄叉基-β-D-葡萄吡喃糖苷（1）经区域选择性地苯甲酰化,得到受体甲基-3-O-苯甲酰基-4,6-O-苄叉基-β-D-葡萄吡喃糖苷（2）。该受体与供体异丙基-2-O-苯甲酰基-3-O-烯丙基-4,6-O-苄叉基-β-D-1-硫代半乳吡喃糖苷（4）偶联,获得了一种保护的二糖Galp（α1→2）Glcp片段甲基-2-O-苯甲酰基-3-O-烯丙基-4,6-O-苄叉基-α-D-半乳吡喃糖基-（1→2）-3-O-苯甲酰基-4,6-O-苄叉基-β-D-葡萄吡喃糖苷（5）。所有的产品通过NMR、MS等方法进行了结构表征。

A novel 1,2-cis stereoselective synthesis of protected α-D-Gal-(1→2)-D-Glc fragments was developed. Methyl 2-O-acetyl-3-O-allyl-4,6-O-benzylidene-α-D-galactopyranosyl-(1→2)-3-O-benzoyl-4,6-O-benzylidene-α-D-glucopyranoside (13), methyl 2-O-acetyl-3-O-allyl-4,6-O-benzylidene-α-D-galactopyranosyl-(1→2)-3,4,6-tri-O-benzoyl-α-D-glucopyranoside (15), methyl 2-O-acetyl-3-O-allyl-4,6-O-benzylidene-α-D-galactopyranosyl-(1→2)-3-O-benzoyl-4,6-O-benzylidene-β-D-glucopyranoside (17), and methyl 2-O-acetyl-3-O-allyl-4,6-O-benzylidene-α-D-galactopyranosyl-(1→2)-3,4,6-tri-O-benzoyl-β-D-glucopyranoside (19) were favorably obtained by coupling a new donor, isopropyl 2-O-acetyl-3-O-allyl-4,6-O-benzylidene-1-thio-β-D-galactopyranoside (2), with acceptors, methyl 3-O-benzoyl-4,6-O-benzylidene-α-D-glucopyranoside (4), methyl 3,4,6-tri-O-benzoyl-α-D-glucopyranoside (5), methyl 3-O-benzoyl-4,6-O-benzylidene-β-D-glucopyranoside (8), and methyl 3,4,6-tri-O-benzoyl-β-D-glucopyranoside (12), respectively. By virtue of the concerted 1,2-cis α-directing action induced by the 3-O-allyl and 4,6-O-benzylidene groups in donor 2 with a C-2 acetyl group capable of neighboring-group participation, the couplings were achieved with a high degree of α selectivity. In particular, higher α/β stereoselective galactosylation (5.0:1.0) was noted in the case of the coupling of donor 2 with acceptor 12 having a β-CH(3) at C-1 and benzoyl groups at C-4 and C-6.

Synthesis of N,N′-bis(2-salicyloyl)isophthalic acid dihydrazide(7) was synthesized with self-made salicylhydrazide(4) and isophthaloyl chloride(5) as raw materials,DMF as a solvent,triethylamine as an antacid,n(isophthaloyl chloride)∶n(salicylhydrazide) = 1.00∶2.75,for 9 h at 90 ℃,the yield was achieved 79.3%.At the same condition,N,N′-bis(2-salicyloyl)terephthalic acid dihydrazide(8) was synthesized,and the yield was 80.2%.The two products were confirmed by 1H NMR and MS etc.,and they were carried with TG analysis and applied research to PVC,and were shown a good thermal stability.

Lamivudine is a 2'-deoxy nucleoside analogue with a biological importance of an anti-HIV and anti-HBV.On the comparison of two technologies that the intermediate menthyl dihydroxy glycoxylate was synthesized with bromoacetic acid or glycoxylic acid as a different raw material,the synthetic technology is discovered shorter steps and lower cost with glycoxylic acid as a raw material.Menthyl dihydroxy glycoxylate was reacted to cyclization with 2,5-dihydroxy-1,4-dithiane,subsequent chlorinated,coupled,and reduced to obtain lamivudine.Meanwhile,the synthesis and separation technology was improved,and the overall yield is reached 22.5%.The improved technology herein is applicable to industrial production as the advantage of shorter steps,concise and practical operation.