Mathews J M, Bend J R
Mol Pharmacol. 1986 Jul;30(1):25-32.
To produce potent, isozyme-selective suicide inhibitors of cytochrome P-450 (P-450), a series of N-alkylated 1-aminobenzotriazole (ABT) derivatives was synthesized; these included the N-methyl, N-butyl (BuBT), N-benzyl (BBT), and N-alpha-methylbenzyl (alpha MB) analogues of ABT. The suicide inhibitors showing the greatest potency and isozyme selectivity were BBT and alpha MB, compounds which included molecular features for P-450 inactivation (the ABT moiety) and similarity to benzphetamine. ABT and its N-alkylated derivatives were tested as suicide inhibitors in rabbit lung microsomes, whose P-450 monooxygenase system has been well characterized in both untreated and beta-naphthoflavone- or 2,3,7,8-tetrachlorodibenzo-p-dioxin-treated animals. ABT (10 mM) destroyed up to 99% of the total P-450 content of lung microsomes of untreated rabbits. At equimolar concentrations (10 microM), ABT was less effective than the N-alkylated compounds for the inhibition of P-450 isozyme 2-catalyzed benzphetamine N-demethylation (BND); in fact, BuBT, BBT, and alpha MB completely inhibited BND activity at this concentration and destroyed less than 40% of total pulmonary P-450. However, these compounds also inactivated 69-85% of isozyme 6-catalyzed 7-ethoxyresorufin O-deethylation. The most potent and isozyme-selective suicide inhibitor prepared was alpha MB: at 1 microM this compound inhibited approximately 80% of isozyme 2-catalyzed and 20% of isozyme 6-catalyzed monooxygenase activity but spared P-450 isozyme 5; at 2.5 microM it caused a near-complete loss (96 +/- 2%) of BND activity. The partition ratio of alpha MB, i.e., the molar ratio of inhibitor present to that of the P-450 destroyed, was 11 +/- 2, further demonstrating the potency of this compound. Experiments with BBT- and sodium phenobarbital-treated rats showed that the mechanism for suicidal inactivation of P-450 by this N-alkylated compound was by benzyne release, the same mechanism demonstrated earlier for the parent compound ABT.
为了制备细胞色素P-450（P-450）的高效、同工酶选择性自杀性抑制剂，合成了一系列N-烷基化的1-氨基苯并三唑（ABT）衍生物；这些衍生物包括ABT的N-甲基、N-丁基（BuBT）、N-苄基（BBT）和N-α-甲基苄基（αMB）类似物。显示出最大效力和同工酶选择性的自杀性抑制剂是BBT和αMB，这些化合物包含P-450失活的分子特征（ABT部分）并且与苄非他明相似。ABT及其N-烷基化衍生物在兔肺微粒体中作为自杀性抑制剂进行了测试，兔肺微粒体的P-450单加氧酶系统在未处理以及经β-萘黄酮或2,3,7,8-四氯二苯并-p-二恶英处理的动物中均已得到充分表征。ABT（10 mM）可破坏未处理兔子肺微粒体中高达99%的总P-450含量。在等摩尔浓度（10 μM）下，ABT在抑制P-450同工酶2催化的苄非他明N-脱甲基化（BND）方面比N-烷基化化合物效果差；事实上，BuBT、BBT和αMB在此浓度下完全抑制了BND活性，并且破坏的肺总P-450不到40%。然而，这些化合物也使同工酶6催化的7-乙氧基试卤灵O-脱乙基化失活了69 - 85%。制备的最有效和同工酶选择性自杀性抑制剂是αMB：在1 μM时，该化合物抑制了约80%的同工酶2催化的和20%的同工酶6催化的单加氧酶活性，但不影响P-450同工酶5；在2.5 μM时，它导致BND活性几乎完全丧失（96±2%）。αMB的分配比，即存在的抑制剂与被破坏的P-450的摩尔比为11±2，进一步证明了该化合物的效力。用BBT和苯巴比妥钠处理大鼠的实验表明，这种N-烷基化化合物使P-450发生自杀性失活的机制是通过苯炔释放，这与母体化合物ABT早期证明的机制相同。
