Isoxazole derivatives as centrally acting muscle relaxants. II Synthesis and structure-activity relationship of 3-amino-N-(3-phenyl-5-isoxazolyl)propanamides.
作者:TOCHIRO TATEE、KAZUHISA NARITA、SHUJI KURASHIGE、SHINJI ITO、HIROSHI MIYAZAKI、HIROSHI YAMANAKA、MICHINAO MIZUGAKI、TAKAO SAKAMOTO、HIDEOMI FUKUDA
DOI:10.1248/cpb.34.1643
日期:——
N-Substituted 3-amino-2-methyl-N-(3-phenyl-5-isoxazolyl)propanamide derivatives (5a-w) were prepared, and their muscle relaxant and anticonvulsant activities were evaluatd. Among the compounds with high potency, 3-diethylamino-2, N-dimethyl-N-(3-phenyl-5-isoxazolyl)propanamide (5e) was found to possess selective muscle relaxant and anticonvulsant activities. Compounds with carbon side chains other than the 2-methylpropanamide moiety did not give increased muscle relaxant activity. Optical isomers of 5e were prepared from metyl (+)-and (-)-3-diethylamino-2-methylpropionates (15a, b), and the (+)-isomer (5x)b was found to be twice as potent as the (-)-isomer (5y). The structure-activity relationship was studied with emphasis on the effects of the 3-amino moiety and of the substituent on the isoxazolyl 5-amino group. A good quadratic correlation equation was found between hydrophobicity and muscle relaxant activity.
制备了 N-取代的 3-氨基-2-甲基-N-(3-苯基-5-异恶唑基)丙酰胺衍生物(5a-w),并评估了它们的肌肉松弛剂和抗惊厥活性。在高效力化合物中,3-二乙基氨基-2, N-二甲基-N-(3-苯基-5-异恶唑基)丙酰胺(5e)具有选择性肌肉松弛和抗惊厥活性。除 2-甲基丙酰胺分子外,具有其他碳侧链的化合物不会增加肌肉松弛活性。由(+)-和(-)-3-二乙氨基-2-甲基丙酸甲酯(15a、b)制备出了 5e 的光学异构体,发现(+)-异构体 (5x)b 的药效是(-)-异构体 (5y) 的两倍。结构与活性关系的研究重点是 3-氨基和异噁唑基 5-氨基上取代基的影响。研究发现,疏水性与肌肉松弛活性之间存在良好的二次相关方程。