Acetic Acid-Driven One-Pot Synthesis of 4,7-dihydro-[1,2,3]thiadiazolo[5,4-b]pyridine-6-carboxamides and Pharmacological Evaluations

ChemMedChem. 2025 Jan 14;20(2):e202400595. doi: 10.1002/cmdc.202400595. Epub 2024 Nov 13.

Abstract

A diverse set of 4,7-dihydro-[1,2,3]thiadiazolo[5,4-b]pyridine-6-carboxamides 4(a-o) was synthesized via a one-pot reaction of 5-amino-[1,2,3]thiadiazole, various aromatic aldehydes, and different acetoacetanilides, using glacial acetic acid. The resulting compounds were obtained in moderate to good yields. All the newly synthesized compounds were evaluated for their antimicrobial activity. Among them, compound 4 e demonstrated superior efficacy against the Salinivibrio proteolyticus strain of Gram-negative bacteria compared to ciprofloxacin. Compound 4 d exhibited the highest potency against the fungal strain Candida albicans, surpassing amphotericin B. The physicochemical characteristics of 4 d and 4 e were assessed. According to docking analysis, DHTDAPy 4 e shows a higher binding affinity of -7.2 kcal/mol in the binding cavity of the receptor. These findings illustrate the safety, tolerability, and potency of the newly synthesized DHTDAPy compounds against fungal and bacterial infections.

Keywords: 4,7-dihydro-[1,2,3]thiadiazolo[5,4-b]pyridine-6-carboxamides; Antimicrobial; Molecular docking; Multicomponent reaction.

MeSH terms

  • Acetic Acid* / chemistry
  • Acetic Acid* / pharmacology
  • Anti-Bacterial Agents* / chemical synthesis
  • Anti-Bacterial Agents* / chemistry
  • Anti-Bacterial Agents* / pharmacology
  • Antifungal Agents* / chemical synthesis
  • Antifungal Agents* / chemistry
  • Antifungal Agents* / pharmacology
  • Candida albicans* / drug effects
  • Dose-Response Relationship, Drug
  • Gram-Negative Bacteria* / drug effects
  • Microbial Sensitivity Tests*
  • Molecular Docking Simulation
  • Molecular Structure
  • Pyridines / chemical synthesis
  • Pyridines / chemistry
  • Pyridines / pharmacology
  • Structure-Activity Relationship
  • Thiadiazoles / chemical synthesis
  • Thiadiazoles / chemistry
  • Thiadiazoles / pharmacology

Substances

  • Antifungal Agents
  • Anti-Bacterial Agents
  • Acetic Acid
  • Thiadiazoles
  • Pyridines