Abstract

COMPARATIVE PHYSICOCHEMICAL CORRELATION STUDY OF SYNTHESIZED PRODRUG AND CODRUG OF ASPIRIN+PARACETAMOL AND INDOMETHACIN+PARACETAMOL BY COVALENT AND NON–COVALENT BONDING

Debojyoti Basu, Divyesh Sharma and Prof. Dr. Dhrubo Jyoti Sen

Abstract

The idea of formation of prodrug and codrug of aspirin with paracetamol & indomethacin with paracetamol has been implemented on the structural entity of these NSAIDs. Prodrug of aspirin/indomethacin and paracetamol has been done by converting free carboxylic acid (–COOH) of aspirin/indomethacin into acid chloride (–COCl); by using thionyl chloride and subsequently this acid chloride has been reacted with free phenolic group (–OH) of paracetamol to get the two desired prodrugs, similarly codrug of aspirin/indomethacin and paracetamol has been formed by co– crystallization technique applied on aspirin with paracetamol and indomethacin with paracetamol to get the codrug of two in precipitated crystals. Physicochemical parameter comparison of individual API (Active Pharmaceutical Ingredient) with synthesized prodrug as well as codrug were done for CHN%, solubility profile, melting point, TLC–Rf, UV spectra, IR spectra, Mass spectra, logP and found that the values differ from the API which shows the significance of prodrug and codrug synthesis. Nonpolarity of prodrug and codrug was found as follows: Prodrug–B (3.94) > Codrug–B (3.42) > Prodrug–A (2.15) > Codrug–A (1.55). Codrugs are found always polar than prodrug because prodrug has covalent bonding between two APIs and codrug has non–covalent interactions such as hydrogen bonding, ionic interactions, Van der Waals interactions and π–interactions between two APIs.

Keywords: API, CHN%, Prodrug, Codrug, Co–crystallization, logP, TLC, UV ?max, IR Spectra, Mass Spectra, Hydrogen bonding, Ionic interactions, Van der Waals interactions, ?– interactions.