aba1a2a1a21A1B122A2Baba“”a1.12.3.24.5.NHOH3CCH2HNNPhentolamineNE(-)a2iv5-HTaþþNNNH2CH3OCH3ONNCOPrazosina2a2-RNEa2yohNHNOHCH3OOCYohimbinpropranolol1AatenololbpindololbbCHCH2NHOHCH(CH3)2CH2OPropranololCHCH2NHOHCH(CH3)2CH2CH2CH2NOOAtenololCHCH2NHOHCH(CH3)2CH2ONHPindololb1.2.3.4.5.6.7.8.9.1.2.3.4.5.b1.90%1-3ht1/22-5h2.60-70%30%3.90%4.125.1.