2,2'-Oxybis-(p-phenylene-methylene)-bis-2-thiopseudourea dihydrochloride 63498-28-2 Pseudourea, 2,2'-oxybis(p-phenylenemethylene)bis(2-thio-, dihydrochloride Pseudourea, 2,2'-oxybis(p-phenylenemethylene)dithiodi-, dihydrochloride USAF DO-15