Preparation and properties of new antitubercular thioureas and thiosemicarbazides

Abstract

Unsymmetrical thioureas and thiosemicarbazides, valuable as lead compounds for antitubercular drug design and discovery, are prepared by the reactions of isothiocyanates with aromatic amines and acid hydrazides, respectively, in robust procedures that permit considerable structural variety. Occasional isolation of symmetrical thioureas derived wholly from the isothiocyanate components of these reactions may occur by thermal fragmentation of the initial thioureidation products.

Keywords:

• Thioureas
• Thiosemicarbazides
• Tuberculosis
• Thermal fragmentation

Acknowledgements

The authors thank the staff of the Tuberculosis Antimicrobial Acquisition and Co-ordinating Facility, co-ordinated by the Southern Research Institute, Birmingham, Alabama, USA, under a research and development contract with the National Institute of Allergy and Infectious Diseases (NIAID) of the US National Institutes of Health (NIH). Mass spectra were determined at the NIH Mass Spectrometry Facility at Michigan State University, East Lansing, Michigan, USA. This work was supported by the Global Alliance for Tuberculosis Drug Development and by grant 1 R15 AI48397-01 from the Division of Acquired Immunodeficiency Syndrome, NIAID, NIH. RWW is grateful to the Howard Hughes Mentoring in Science Program. MJH thanks Wellesley College for the grant of a sabbatical.