Molecular Diversity

, Volume 19, Issue 4, pp 653–667 | Cite as

Regioselective alkylation of 1,3,4,5-tetrahydrobenzo[d]azepin-2-one and biological evaluation of the resulting alkylated products as potentially selective \(\hbox {5-HT}_{\mathrm{2C}}\) agonists

  • Navnit Prajapati
  • Rajani Giridhar
  • Anshuman Sinha
  • Ashish M. Kanhed
  • Mange Ram Yadav
Full-Length Paper


The benzazepine ring system has offered interesting CNS-active medicinal agents. Taking this privileged structure as the basic scaffold, \(\hbox {C}_{1}\) and/or \(\hbox {N}_{3}\)-alkylated benzazepin-2-one derivatives and their reduced analogs have been prepared as potential \(\hbox {5-HT}_{\mathrm{2C}}\) receptor agonists. The selective alkylation at the \(\hbox {C}_{1}\) and/or \(\hbox {N}_{3}\) positions of this seven-membered lactam ring is here reported for the first time under different reaction conditions. The synthesized compounds were evaluated for their biological profile as potential \(\hbox {5-HT}_{\mathrm{2C}}\) agonists using a classic pharmacological approach. Three derivatives (15, 17, and 20) have shown promising \(\hbox {5-HT}_{\mathrm{2C}}\) agonistic activity which can be further optimized as anti-obesity agents for the treatment of male sexual dysfunction. Further, a homology model for \(\hbox {5-HT}_{\mathrm{2C}}\) receptor was generated using MODELLER, and ligand–receptor interactions for these potential molecules were studied.


3-Benzazepine Regioselective alkylation Phenethyl fragment Selective \(\hbox {5-HT}_{\mathrm{2C}}\) agonists Anti-obesity agents 



The authors thank the Director, SAIF-Division, Panjab University, Chandigarh for their help. Navnit Prajapati, Anshuman Sinha, and Ashish M. Kanhed thank UGC, New Delhi for BSR-RFSMS-fellowship (No.F.4-1/2006 BSR/7-129/2007 BSR).

Conflict of interest

The author(s) confirm that there is no conflict of interest on the contents of this article.

Supplementary material

11030_2015_9600_MOESM1_ESM.docx (5.7 mb)
Supplementary material 1 (docx 5876 KB)


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Navnit Prajapati
    • 1
  • Rajani Giridhar
    • 1
  • Anshuman Sinha
    • 1
  • Ashish M. Kanhed
    • 1
  • Mange Ram Yadav
    • 1
  1. 1.Faculty of Technology & Engineering, KalabhavanThe M. S. University of BarodaVadodaraIndia

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