During previous work investigating the BCA2-inhibitory activity
of disulfiram analogues, we synthesized a small series of carbamo(
dithioperoxo)thioates by heating a mixture of disulfiram
(or related piperidinyl or pyrrolidinyl analogues) with alkyl thiols
in ethanol under reflux (Scheme 1).2 This procedure led to the formation
of the required carbamo(dithioperoxo)thioate products in
low yields (9–25%) following extensive column chromatography,
alongside a number of mixed disulfide-based by-products
Testing of new disulfiram analogues and the structurally related
carbamo(dithioperoxo)thioates in human breast cancer cell lines
with differing levels of expression of BCA2, including the isogenic
cell lines MDA-MB-231 (BCAlow/) and MDA-MB-231/ER (BCA2+),
revealed interesting results.2 Of particular note were the carbamo(
dithioperoxo)thioates derived from reaction of disulfiram