Design of resistance-surmountable HIV protease inhibitors based on molecular recognition analysis of mutant protease

具有新作用机制的HIV蛋白酶抑制剂作为抗HIV药物的出现，为艾滋病的综合治疗提供了新的发展方向。然而，目前的HIV蛋白酶抑制剂在剂量、经济性、毒副作用、耐药性、中枢转运等方面还存在许多问题，为了克服这些问题，我们在分子识别分析的基础上，设计合成了含有理想的过渡态模拟物羟甲基羰基（HMC）等排体的小分子HIV蛋白酶抑制剂。小尺寸和高效力的抑制剂在成本和抗性诱导方面也是有利的，因为分子识别研究表明这些抑制剂在较少的位点与酶相互作用。此外，与逆转录酶抑制剂缀合的混合型抗HIV药物可以表现出更好的细胞膜渗透性，以及协同效应，从而导致实际的耐药性可克服的第三代HIV蛋白酶抑制剂。因此，我们获得了一种由二肽KNI-727与逆转录酶抑制剂AZT通过可自发裂解的接头缀合组成的高效“双重药物”。我们还利用分子内酰基迁移反应合成了水溶性的前药，成功地控制了前药中活性分子的释放时间;在新的设计方面，我们合成了含L-四氢呋喃甘氨酸的抑制剂，表明抑制剂与酶的S2位点有良好的相互作用。P1-P1'位含有羟甲基羰基酰肼的伪对称抑制剂对HIV蛋白酶有较强的抑制活性，二肽抑制剂KNI-727和KNI-764则选择性抑制在疟原虫增殖中起重要作用的天冬氨酸蛋白酶家族的plasmepsin Ⅱ。因此，我们表明，我们的抑制剂设计方法广泛适用于抑制来自各种来源的天冬氨酸蛋白酶。

Introduction of HIV protease inhibitors with new action mechanism as anti-HIV drugs provided a new development in the combination therapy of AIDS. However, there are many problems to be solved such as dose, economics, side effects, resistance, transport to central nervous system.In order to overcome these problems, we designed and synthesized small-sized HIV protease inhibitors containing hydroxymethylcarbonyl (HMC) isostere, an ideal transition state mimic, based on the data obtained from molecular recognition analysis. Inhibitors of small size and high potency are advantageous in terms of cost and resistance induction as well because molecular recognition studies showed that these inhibitors interacts with the enzyme at fewer sites. Furthermore, hybrid-type anti-HIV drugs conjugated with reverse transcriptase inhibitors may exhibit better cell membrane permeability, and synergistic effect leading to practical resistance-surmountable HIV protease inhibitors of third generation. As a result, we obtained a highly potent 'double-drug' consisting of dipeptide, KNI-727 conjugated with a reverse transcriptase inhibitor, AZT through a spontaneously cleavable linker. We also synthesized water soluble prodrugs using intramolecular acyl migration reaction and succeeded to control the releasing time of the active molecules from the prodrugs.In the new design aspect, we synthesized inhibitors containing L-tetrahydrofuranylglicine to show that the inhibitors interacts favorably with the enzyme at the S2 site. Pseudo-symmetric inhibitors containing hydroxymethylcarbonyl hydrazide at P1-P1' position exhibited high HIV protease inhibitory activity.Alternatively, dipeptide inhibitors, KNI-727 and KNI-764 selectively inhibited plasmepsin II which plays important role in the proliferation of malaria parasite and belongs to the aspartic protease family. Thus, we showed that our inhibitor design methodology is widely applicable to inhibit aspartic proteases from various origins.