申请人:NERVIANO MEDICAL SCIENCES S.R.L.
公开号:US10174048B2
公开(公告)日:2019-01-08
The present invention relates to a new process for the preparation of thieno-indole derivatives of formula (Ia) or (Ib), exploiting an asymmetric synthesis for the preparation of key (8S) or (8R) 8-(halomethyl)-1-alkyl-7,8-dihydro-6H-thieno[3,2-e]indol-4-ol intermediates, and to useful intermediate compounds of such process. Thieno-indole derivatives are described and claimed in GB2344818, WO2013/149948 and WO2013/149946, which also disclose processes for their preparation. Thieno-indole enantiopure derivatives can now be advantageously prepared through a new asymmetric synthesis of the key 8-(halomethyl)-7,8-dihydro-6H-thieno[3,2-e]indol intermediates, which, avoiding the chiral resolution step, provides benefits in terms of reducing time and costs of the whole process for their preparation. The synthesis starts from the N-alkylation of 5-amino-4-halo-3-alkyl-1-benzothiophene-7-ol derivatives with enantiopure glycidyl 3-nosylate, followed by intramolecular 6-endo-tet cyclization using alkyl Grignard reagents; Mitsunobu activation of the secondary alcohol promotes internal spirocyclization, affording the 4,4a,5,6-tetrahydro-8H-cyclopropa[c]thieno[3,2-e]indol-8-one derivatives; finally, stereo-electronically controlled regioselective cyclopropane opening yields the key enantiopure 8-(halomethyl)-1-alkyl-7,8-dihydro-6H-thieno[3,2-e]indol-4-ol intermediates, which can be further derivatized following teachings disclosed in WO2013/149948 or WO2013/149946, to prepare the final thieno-indole derivatives of formula (Ia) or (Ib). Such compounds are disclosed to be alkylating compounds with cytotoxic activity, therefore useful as such in the treatment of a variety of cancers and in cell proliferative disorders, or, conjugated with different types of nucleophiles, in the preparation of Antibody Drug Conjugated derivatives.
本发明涉及一种制备式(Ia)或(Ib)噻吩-吲哚衍生物的新工艺,利用不对称合成制备关键的(8S)或(8R)8-(卤甲基)-1-烷基-7,8-二氢-6H-噻吩并[3,2-e]吲哚-4-醇中间体,以及该工艺的有用中间体化合物。噻吩-吲哚衍生物在 GB2344818、WO2013/149948 和 WO2013/149946 中均有描述和权利要求,其中还公开了其制备工艺。现在,通过对关键的 8-(卤甲基)-7,8-二氢-6H-噻吩并[3,2-e]吲哚中间体进行新的不对称合成,就可以制备出噻吩并吲哚对映体纯衍生物,该方法避免了手性解析步骤,在减少整个制备过程的时间和成本方面具有优势。该合成首先用 3-对映体缩水甘油酸酯对 5-氨基-4-卤-3-烷基-1-苯并噻吩-7-醇衍生物进行 N-烷基化,然后用烷基格氏试剂进行分子内 6-内向四环化;仲醇的 Mitsunobu 活化促进了内部螺环化,从而得到 4,4a,5,6-四氢-8H-环丙[c]噻吩并[3,2-e]吲哚-8-酮衍生物;最后,立体电子控制的区域选择性环丙烷开环产生关键的不对映纯的 8-(卤甲基)-1-烷基-7,8-二氢-6H-噻吩并[3,2-e]吲哚-4-醇中间体,这些中间体可以按照 WO2013/149948 或 WO2013/149946 中公开的方法进一步衍生,制备最终的式 (Ia) 或 (Ib) 的噻吩-吲哚衍生物。此类化合物被公开为具有细胞毒性活性的烷基化化合物,因此可用于治疗各种癌症和细胞增殖性疾病,或与不同类型的亲核物共轭,制备抗体药物共轭衍生物。