Harries' dipyrogallol or 2,3,4,2',3',4'-hexahydroxydiphenyl,though a compound with the possibility of multiple antimonation on the odiphenol units,forms with either excess of antimony trichloride in saturated sodium chloride or excess of tartar emetic in aqueous solution,a sole 1:1 antimonyl compound.The antimonyl dipy rogallol is almost insoluble in N hydrochloric acid,but can be recrystallized with 2N hydrochloric acid,whereas in 3 N (or more concentrated) hydrochloric acid,it is completely hydrolyzed,regenerating quantitatively the original dipyrogallol.Harries' dipyrogallol has been found to crystallize in two forms:the needles (anhydrous),and the prisms (monohydrate).