thiocarboxylic acids

https://doi.org/10.1351/goldbook.T06352
Compounds in which one or both oxygens of a carboxy group have been replaced by divalent sulfur RC(=O)SH or RC(=S)OH monothiocarboxylic acids, RC(=S)SH dithiocarboxylic acids.
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1372 [Terms] [Paper]