An efficient approach for the synthesis of novel methyl sulfones in acetic acid medium and evaluation of antimicrobial activity.

Gollapudi Ravi Kumar,Vijay Kotra,Ravi Varala,Hari Babu Bollikolla,Chandra Rao Dasireddy

doi:10.3906/kim-2003-10

Abstract

A series of nine methyl sulphones ( 3a –3 i ) starting from the aldehydes ( 1a–1i ) were synthesized in two consecutive steps. In the first step, preparation of allyl alcohols ( 2a–2i ) from their corresponding aldehydes by the reaction of sodium borohydride in methanol at room temperature is reported. Finally, methyl sulphones are synthesized by condensing sodium methyl sulfinates with allyl alcohols in the presence of BF 3 .Et 2 O in acetic acid medium at room temperature for about 2–3 h. The reaction conditions are simple, yields are high (85%–95%), and the products were obtained with good purity. All the synthesized compounds were characterized by their 1 H, 13 C NMR, and mass spectral analysis. All the title compounds were screened for antimicrobial activity. Among the compounds tested, the compound 3f has inhibited both Gram positive and Gram negative bacteria effectively and compound 3i has shown potent antifungal activity. These promising components may help to develop more potent drugs in the near future for the treatment of bacterial and fungal infections.

Highlights

The alcohol functional group is one of the more important groups for the synthesis of many drugs which are being used widely throughout the world [1,2,3,4,5]
Earlier works revealed that direct conversion of alcohols into sulfones using bronsted acids like formic acids, acetic acid, and HCl [17,18,19,20], could be generated from sodium sulfide, sodium sulfinates, sulfonic acids, potassium meta bisulfite, sulfonyl chloride, and arenesulfonyl cyanide [21,22,23,24,25,26,27]
Huang et al [32] reported on the synthesis of sulfinates using BF3.OEt2 in CH2Cl2 solvent medium optimized at 45–50 °C moderate temperatures via the more favourable SN1 mechanism through the conversion of sodium p-toluenesulfinate into corresponding nucleophile sulfinic acid, i.e. O-attack

Summary

Introduction

The alcohol functional group is one of the more important groups for the synthesis of many drugs which are being used widely throughout the world [1,2,3,4,5]. Direct substitution of alcohols in the presence of boron trifluoride etherate with sodium sulfinates was prepared in which dichloromethane as a solvent was used under optimized parameters at 50 °C with 82% yield [32]. Huang et al [32] reported on the synthesis of sulfinates using BF3.OEt2 in CH2Cl2 solvent medium optimized at 45–50 °C moderate temperatures via the more favourable SN1 mechanism through the conversion of sodium p-toluenesulfinate into corresponding nucleophile sulfinic acid, i.e. O-attack. The best yield (95%) of the desired molecule was obtained with the nitro alcohol derivatives (3i), under the optimized reaction condition.

Conclusion

Findings

Experimental section