【作者】 张美慧；

【导师】 程卯生； 木曾良明；

【作者基本信息】 沈阳药科大学 ， 药物化学， 2008， 博士

【摘要】 人类T细胞白血病病毒Ⅰ型（HTLV-Ⅰ）的感染可以导致成人T细胞白血病（ATI）和热带痉挛性下肢瘫痪/HTLV-Ⅰ相关脊髓病（TSP/HAM）等其他慢性疾病,目前全世界范围内有2-3千万人为病毒携带者。HTLV-Ⅰ蛋白酶与这一病毒的复制密切相关,抑制蛋白酶的活性能够有效地阻止病毒的复制。因此,HTLV-Ⅰ蛋白酶是一个非常重要的抗HTLV-Ⅰ感染的研究靶点。天然肽分子易于被体内的酶降解而失去活性,本文设计将含有羟甲羰基（HMC）结构的（2S,3S）-3-氨基-2-羟基-4-苯基丁酸（Apns）作为非天然氨基酸残基,引入底物的结构中,模拟天然底物被蛋白酶水解的过渡态类似物,从而阻断天然底物与酶的结合,有效抑制HTLV-Ⅰ蛋白酶活性。以KNI-10455(IC₅₀=140nM)作为先导化合物,在C端和N端引入不同的取代胺基和取代羧基,并逐步减小分子结构,通过液相合成的方法制备了66个未见文献报道的拟肽类化合物,其中53个为四肽化合物,9个为三肽化合物,4个为二肽化合物。新化合物的结构经核磁共振氢谱和质谱检测确证。采用蛋白酶抑制剂活性测定方法对新化合物进行了初步抗HTLV-Ⅰ和HIV-1蛋白酶活性筛选。结果显示53个四肽化合物在50nM浓度下显示了较高的HIV-1蛋白酶抑制率（＞97%）;42个四肽抑制剂具有高于先导化合物的抗HTLV-Ⅰ蛋白酶活性(IC₅₀＜137nM);二肽和三肽化合物在600nM浓度下对HTLV-Ⅰ蛋白酶没有显著的抑制作用（＜14%）;其中活性最强的化合物是（R）-N-（2,2-二甲基）丙基-3-{{（2S,3S）-3-{(2S-2-[（2S）-2-丁酰胺基-2-苯基]乙酰胺基-3,3-二甲基}丁酰胺基-2-羟基-4-苯基}}丁酰基-5,5-二甲基-1,3-噻唑-4-甲酰胺(IC₅₀=74 nM)。更多还原

【Abstract】 A large number of diseases including adult T-cell leukemia（ATL） and tropical spastic paraparesis/HTLV-I-associated myelopathy（TSP/HAM） are caused by the human T-cell leukemia virus typeⅠ（HTLV-I）.HTLV-I infection is currently considered as an intractable disease because 20-30 million individuals worldwide are viral carriers.HTLV-I protease is responsible for the proliferation of the retrovirus and then becomes an attractive target for developing inhibitors against HTLV-I infections.Substrates containing natural amino acid residues are easily digested by proteases. When a non-natural amino acid,（2S,3S）-3-amino-2-hydroxy-4-phenylbutyric acid（Apns）, containing a hydroxymethylcarbonyl（HMC） isostere,that can mimic the tetrahedral transition-state of amino bond hydrolysis but cannot itself be hydrolyzed by the enzyme,is introduced,the protease’s pharmacological actions are suspended.Using KNI-10455 as a reference compound(IC₅₀=140 nM),we were interested in modifying the N-and C-terminals and truncation studies to enhance HTLV-I protease inhibition.Sixty-six peptidic compounds containing Apns were prepared by solution phase peptide synthesis.Fifty-three of them were tetrapeptidic inhibitors.Nine of them were tripeptidic compounds.Four of them were dipeptidic inhibitors.The structures were identified by ¹H-NMR and MS spectra.All novel compounds were evaluated for HTLV-I and HIV-1 protease assays. Fifty-three tetrapeptides exhibited high HIV-1 protease inhibition at 50nM（＞97%）.Forty-two tetrapeptides showed potent HTLV-I protease activity(IC₅₀＜137nM) that were greater than the reference compound.None of the tri-and di-peptides efficiently inhibited HTLV-I protease at 600 nM（＜14%）.The most potent HTLV-I protease inhibitor was（R）-N-（2,2-dimethyl） propyl-3-{{（2S,3S）-3-{（2S）-2-[（2S）-2-butyrylamino-2-phenyl]acetylamino-3,3-dimethyl}butan oylamino-2-hydroxy-4-phenyl}}butanoyl-5,5-dimethyl-l,3-thiazolidine-4-carboxamide(IC₅₀= 74nM).更多还原