Process for the preparation of 2-substituted-2-(6-(substituted)-7-methylbenzo[D][1,3]dioxol-4-yl)acetic acid derivatives
申请人:Natco Pharma Limited
公开号:US09227948B2
公开(公告)日:2016-01-05
Present invention relates to an improved and commercial process for the preparation of 2-sustituted-2-(6-(substituted)-7-methylbenzo[d][1,3]dioxol-4-yl)acetic acid derivatives of formula-I the above Formula I, XII, XIII, XV, wherein R1 is a O-protecting group such as methoxymethyl, ethoxymethyl, trialkylsilyl, arylmethyl, tetrahydropyran-2-yl, allyl; X is hydroxyl, halogen, mesylate, triflate, tosylate, acetate; Y is oxygen atom, NH or sulfur atom; R2 is C1-C6 alkyl. 2,4-Dihydroxy-3-methylbenzaldehyde is selectively protected at C-4 position in the form of an ether compound of formula-XII, oxidized the aldehyde function to get the diol of formula-XIII, and condensed with ethyl glyoxalate under Casiraghi reaction conditions to get the compound of formula-XV. Compound of formula-XV is converted to compound of formula-I by conventional chemistry. Compounds of formula-I are key intermediates in the synthesis of ecteinascidines like trabectedin.
本发明涉及一种改进的商业化制备2-取代-2-(6-(取代)-7-甲基苯并[d][1,3]二氧杂环-4-基)乙酸衍生物的过程,其化学式为I,XII,XIII,XV,其中R1是O-保护基,例如甲氧甲基,乙氧甲基,三烷基硅基,芳基甲基,四氢吡喃-2-基,烯丙基;X是羟基,卤素,甲磺酸酯,三氟甲磺酸酯,对甲苯磺酸酯,乙酸酯;Y是氧原子,NH或硫原子;R2是C1-C6烷基。2,4-二羟基-3-甲基苯甲醛在C-4位选择性地以醚化合物的形式保护,将醛基氧化得到化合物XIII的二醇,然后在Casiraghi反应条件下与乙酰乙酸乙酯缩合得到化合物XV。化合物XV通过常规化学转化为化合物I。化合物I是合成类似于曲贝特定的Ecteinascidines的关键中间体。