Compounds having the structure acyl-S-acyl. Also called diacylsulfanes, e.g.
CH3C(=O)SC(=S)CH2CH3
acetic thiopropanoic thioanhydride.
Source:
PAC, 1995, 67, 1307
(Glossary of class names of organic compounds and reactivity intermediates based on
structure (IUPAC Recommendations 1995))
on page 1372