Magill A, O'Yang C, Powell M F
Institute of Organic Chemistry, Syntex Research, Palo Alto, California 94304.
Pharm Res. 1988 Apr;5(4):214-9. doi: 10.1023/a:1015937628492.
Prostacyclin analogue 5 undergoes specific acid-catalyzed hydration (kH+ = 1.9 x 10(-7)M-1 sec-1 at 25 degrees C) and a pH-independent oxidation reaction (k0 = 1.2 x 10(-10) sec-1 at 25 degrees C) above pH approximately 5. The hydration reaction for 5 is much slower than for other structurally similar exocyclic alkenes, even though the rate-determining step is proton transfer. This slowness of reaction and an analysis of the pH-rate profile show that 5 does not exhibit significant intramolecular general acid catalysis, as does prostacyclin.
前列环素类似物5在特定条件下会发生酸催化的水合反应（25℃时，kH+ = 1.9×10⁻⁷M⁻¹·s⁻¹），且在pH约为5以上时会发生与pH无关的氧化反应（25℃时，k0 = 1.2×10⁻¹⁰s⁻¹）。5的水合反应比其他结构类似的环外烯烃慢得多，尽管速率决定步骤是质子转移。反应的缓慢以及对pH-速率曲线的分析表明，5不像前列环素那样表现出显著的分子内一般酸催化作用。
