Yohimbine hydrochloride Chemical Properties Melting point 288-290 °C (dec.)(lit.) alpha 99 º (c=1%, H2O, dry subst) refractive index 103 ° (C=1, H2O) storage temp. Refrigerator solubility H2O: 10 mg/mL form powder color white to off-white optical activity [α]/D 100±5°, c = 1 in H2O