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. 2015 Oct 18;84(3):447-455.
doi: 10.3390/scipharm84030447.

A Facile, Improved Synthesis of Sildenafil and Its Analogues

Ambati V Raghava Reddy  1   2 , Garaga Srinivas  3 , Chandiran Takshinamoorthy  4 , Badarinadh Gupta Peruri  5 , Andra Naidu  6
Affiliations

A Facile, Improved Synthesis of Sildenafil and Its Analogues

Ambati V Raghava Reddy et al. Sci Pharm. .

Abstract

This paper describes the facile synthesis of sildenafil citrate (1) and its related compounds through an improved chlorosulfonation reaction using chlorosulfonic acid and thionyl chloride. This synthesis results in pure sildenafil with high yield. The structures of the compounds were determined with infrared (IR), ¹H-NMR and 13C-NMR spectroscopic methods, and high resolution mass spectroscopy (HRMS) analysis.

Keywords: chlorosulfonation; novel analogues; sildenafil.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Structure of sildenafil citrate (1).
Scheme 1
Scheme 1
Reported route for synthesis of sildenafil citrate.
Scheme 2
Scheme 2
Synthetic path of chlorosulfonation.
Scheme 3
Scheme 3
Synthetic route for sildenafil-related compounds.
See this image and copyright information in PMC

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