申请人:ELI LILLY AND COMPANY
公开号:EP0034924A2
公开(公告)日:1981-09-02
A process is described for preparing a 3-iodomethyl cephalosporin of the formula
which comprisesreacting in an aprotic solvent under substantially anhydrous conditions at a temperature between about 0°C and about 35°C a 3-alkanoylmethyl or 3-carbamoyloxymethyl cephalosporin oftheformula
with a trialkylsilyl iodide of the formula
where in the above formulas R is the residue of a carboxylic acid as defined in the specification;
Ro is hydrogen or methoxy;
R1 is C1-C4 alkyl, 2,2,2-trichloroethyl, iodomethyl, diphenylmethyl, benzyl, substituted benzyl substituted by methyl, methoxy or nitro; or R is a trialkylsilyl group of the formula
wherein R3, R3, and R-3; are independentlyC1-C3alkyl; orR1 is sodium or potassium;
R'1 has the same meanings as R1, provided that, when R is sodium, potasstum. diphenylmethyl, or p-methoxybenzyl, R'1 is
R2 is C1-C4 alkanoyloxy or a carbamoyloxy group of the formula
wherein R'2 and R"2 are independently hydrogen or C1-C3 alkyl; and
nis 0 or 1;
with the limitation that when n is 1, the double bond represented by the dotted bonding lines is in the 3-position. The 3-iodomethyl cephalosporins are useful intermediates for antibiotics.
一种制备式 3-碘甲基头孢菌素的工艺包括
其中包括在基本无水的条件下,在约 0°C 至约 35°C 的温度下,在无水溶剂中将式中的 3-烷酰甲基或 3-氨基甲酰氧甲基头孢菌素与式中的三烷基硅碘化物反应
与式中的三烷基硅烷基碘化物反应
在上述公式中,R 是说明书中定义的羧酸残基;
Ro 是氢或甲氧基;
R1 是 C1-C4 烷基、2,2,2-三氯乙基、碘甲基、二苯甲基、苄基、被甲基、甲氧基或硝基取代的取代苄基;或 R 是式中的三烷基硅基
其中 R3、R3 和 R-3 独立地为 C1-C3 烷基;或 R1 为钠或钾;
R'1 的含义与 R1 相同,但当 R 是钠、钾、二苯甲基或对甲氧基苄基时,R'1 是
R2 是式中的 C1-C4 烷酰氧基或氨基甲酰氧基。
其中 R'2 和 R "2 独立地为氢或 C1-C3 烷基;以及
n 为 0 或 1;
但当 n 为 1 时,虚线所代表的双键位于 3 位。3-iodomethyl cephalosporins 是抗生素的有用中间体。