Synthesis and antitumor evaluation of novel Benzo[d]pyrrolo[2,1-b]thiazole derivatives

• Published in: European journal of medicinal chemistry 2012-07, Vol.53, p.28-40
• Main Authors: Chaniyara, Ravi, Tala, Satishkumar, Chen, Chi-Wei, Lee, Pei-Chih, Kakadiya, Rajesh, Dong, Huajin, Marvania, Bhavin, Chen, Ching-Huang, Chou, Ting-Chao, Lee, Te-Chang, Shah, Anamik, Su, Tsann-Long
• Format: Article
• Language: English
• Subjects: Animals; Antineoplastic Agents - chemical synthesis; Antineoplastic Agents - chemistry; Antineoplastic Agents - pharmacology; Antitumor agents; benzo[d]pyrrolo[2,1-b]thiazol; Biological and medical sciences; Cell cycle; Cell Cycle - drug effects; Cell Line, Tumor; Cell Proliferation - drug effects; Chemistry Techniques, Synthetic; Cytotoxicity; DNA - chemistry; DNA cross-linking; Humans; Inhibitory Concentration 50; Male; Medical sciences; Mice; Miscellaneous; Pharmacology. Drug treatments; Thiazoles - chemical synthesis; Thiazoles - chemistry; Thiazoles - pharmacology; Xenograft Model Antitumor Assays
• ISSN: 0223-5234; 1768-3254
• DOI: 10.1016/j.ejmech.2012.03.030

A series of novel 2,3-bis(hydroxymethyl)benzo[d]pyrrolo[2,1-b]thiazoles and their bis(alkylcarbamate) derivatives were synthesized starting from benzothiazole via reaction with dimethyl acetylenedicarboxylate (DMAD)/tetra-fluoro boric acid, catalytic hydrogenation, and alkylcarbamoylation. The anti-proliferative activity of these agents against human leukemia and various solid tumor cell growth in vitro was studied. The structure–activity relationship studies revealed that the bis(alkylcarbamates) derivatives are generally more cytotoxic than the corresponding bis(hydroxymethyl) congeners in inhibiting human lymphoblastic leukemia CCRF-CEM and various human solid tumor cell growth in culture. These agents have no cross-resistance to taxol or vinblastine. Studies on the therapeutic effect against human breast carcinoma MX-1 xenograft showed that complete tumor remission (CR) were achieved by treating with C1-4′-F- or C1-4′-Cl-Ph-bis(i-propylcarbamates) derivatives (19b and 19c, respectively) and more than 99% tumor suppression by the corresponding bis(ethylcarbamates) 18b and 18c at the maximal tolerated dose. Alkaline agarose gel shifting assay revealed that the newly synthesized compounds are able to induce DNA interstrand cross-linking. The present studies generated a series of new potent DNA interstrand cross-linking agents, which have potential for further antitumor drug development. [Display omitted] ► A series of novel benzo[d]pyrrolo[2,1-b]thiazole derivatives were synthesized. ► Evaluated for their antitumor activities both in vitro and in vivo. ► Compound 18b, 19b and 19c exhibited potent therapeutic efficacy in xenograft model. ► The newly synthesized compounds were able to induce DNA interstrand cross-linking.