The title compound (19), a conjugate of a trisaccharide based upon the repeating trisaccharide of α-D-rhamnose, which comprises the polysaccharide portion of "A-band" lipopolysaccharide from a mutant (AK1401) of Pseudomonas aeruginosa, strain PAOl, with bovine serum albumin (BSA) was synthesized starting with methyl α-D-mannopyranoside. Suitably protected D-rhamnose derivatives, namely, ethyl 3,4-di-O-benzyl-1-thio-α-D-rhamnopyranoside (11) and 3-O-acetyl-2,4-di-O-benzyl-α-D-rhamnopyranosyl chloride (12), were used as the glycosyl acceptor and donor, respectively, in the synthesis of disaccharide 13. O-Deacetylation of 13 gave 14, a glycosyl acceptor that reacted with 12 to yield the trisaccharide 15. N-Iodosuccinimide – trifluoromethanesulfonic acid was used as an activator of the thioglycoside in the synthesis of 16 and 17 from 15. Compound 16 was converted into the hydrazide 18 by treatment with hydrazine. The conjugation was achieved by coupling of the intermediate acyl azide derivative of 18 with BSA.
该文献合成了一种标题化合物(19),它是基于α-D-鼠李糖重复三糖的三糖衍生物,该三糖衍生物构成了铜绿假单胞菌(Pseudomonas aeruginosa)PAOl菌株的突变体(AK1401)“A-band”脂多糖的多糖部分,与牛血清白蛋白(BSA)结合。该合成从甲基α-D-甘露糖起始。适当保护的D-鼠李糖衍生物,即3,4-二-O-苯甲酰基-1-硫代-α-D-鼠李糖吡喃糖(11)和3-O-乙酰基-2,4-二-O-苯甲酰基-α-D-鼠李糖吡喃糖氯化物(12),分别用作糖基受体和给体,在二糖13的合成中使用。对13的O-去乙酰化产生14,这是一种糖基受体,它与12反应形成三糖15。在15的合成中,N-碘代琥珀酰亚胺-三氟甲磺酸被用作巯基糖苷的活化剂,用于合成16和17。通过用肼处理16,将其转化为肼酸盐18。通过将18的中间酰基叠氮衍生物与BSA偶联,实现了共轭。