Process for converting the 13-.alpha.-hydroxy group of avermectin
aglycones
    1.
    发明授权
    Process for converting the 13-.alpha.-hydroxy group of avermectin aglycones 失效
    转化阿维菌素糖苷配基的13-α-羟基的方法

    公开(公告)号:US5241083A

    公开(公告)日:1993-08-31

    申请号:US907429

    申请日:1992-07-01

    IPC分类号: C07D493/22

    CPC分类号: C07D493/22

    摘要: The natural stereochemistry at the 13-position of avermectin aglycones, normally .alpha.-oriented or below the plane of the molecule, is inverted or epimerized into the .beta.-position. The procedure starts with the avermectin aglycone compounds where the 13.alpha.-hydroxy group is activated to a mesylate leaving group. The resultant 13-.alpha.-mesylate is then displaced with a cesium carboxylate and one equivalent of the respective carboxylic acid, ending with the ester group being converted to the 13-.beta.-hydroxy configuration by transesterification in high yield.

    摘要翻译: 阿维菌素糖苷配基的13位天然立体化学,通常为α取向或低于分子平面,被倒置或差向异构化成β位。 该程序从其中13α-羟基被活化成甲磺酸酯离去基团的除虫菌素苷元化合物开始。 然后用羧酸铯和1当量相应的羧酸置换所得的13-α-甲酸盐,以酯基转移为最终,酯基以高产率转化为13-β-羟基构型。

    Process for the preparation of imidazolutidine
    3.
    发明授权
    Process for the preparation of imidazolutidine 失效
    咪唑啉胺的制备方法

    公开(公告)号:US5424432A

    公开(公告)日:1995-06-13

    申请号:US249425

    申请日:1994-05-26

    IPC分类号: C07D471/04

    CPC分类号: C07D471/04

    摘要: This invention relates to a method for the preparation of a compound of formula I: ##STR1## a key intermediate in the synthesis of a series of Angiotensin II receptor antagonists. The invention also relates to a selective reagent for conducting the Hofmann rearrangement, particularly in the formation of a pyridinoimidazolone, which is a percursor to the formation of an imidazopyfidine of formula I. This invention also relates to a method for the preparation of imidazolutidine, a key intermediate in the synthesis of 3-(2'-(N-benzoyl)sulfonamidobiphen-4-yl)-methyl-5,7 -dimethyl-2-ethyl-3H-imidazo[4,5-b]pyridine, using pyridinoimidazolone, an unreactive urea.

    摘要翻译: 本发明涉及一种制备式I化合物的方法:作为合成一系列血管紧张素II受体拮抗剂的关键中间体。 本发明还涉及用于进行霍夫曼重排的选择性试剂,特别是形成吡啶并咪唑酮,该吡啶并咪唑酮是形成式I咪唑吡啶的方法。本发明还涉及制备咪唑烷丁的方法, 使用吡啶并咪唑啉酮合成3-(2' - (N-苯甲酰基)磺酰胺联苯-4-基) - 甲基-5,7-二甲基-2-乙基-3H-咪唑并[4,5-b]吡啶的关键中间体 ,非反应性尿素。