Profile: Zhejiang Oma Pharmaceutical Co., Ltd. produces pharmaceutical intermediates and active pharmaceutical ingredients (APIs). We are ISO 9001 certified. We produce guanine, guanine hydrochloride, 2, 9-diacetyl guanine, xanthine, tioguanine and 1, 4-diacetoxy-2-oxabutane. The guanine is a white or cream white powder used as an intermediate of API. The xanthine is an off-white to yellowish crystalline powder used in organic synthesis.