In chemistry, hexol is a cation with formula {[Co(NH)(OH)]Co} — a coordination complex consisting of four cobalt cations in oxidation state +3, twelve ammonia molecules , and six hydroxy anions , with a net charge of +6.  The hydroxy groups act as bridges between the central cobalt atom and the other three, which carry the ammonia ligands. 
Salts of hexol, such as the sulfate {[Co(NH)(OH)]Co}(SO)(HO), are of historical significance as the first synthetic non-carbon-containing chiral compounds.