Enzyme Inhibitors as Potential Anticancer and Antiviral

A.蛋白激酶C项目为了达到完全同工酶特异性的目标，被设计成有效PKC配体的合成dag内酯的范围在不断扩大。今年的主要发现有：1)在固相载体上继续合成额外的96个成员文库，目的是最大限度地探索蛋白质-膜界面结合位点周围的化学空间。新的化学改进在合成和表征库成员的质谱继续进行。2)首次发现了靶向含有C1结构域的非激酶蛋白的dag -内酯。该化合物对RasGRP具有较低的纳摩尔结合亲和力，而对PK-C同工酶的结合活性较弱。目前正在探索这种选择性结合的生物学后果。3)完成了以乙炔单元和苯环交替构成的侧链“刚性棒”形式的dag -内酯的合成。初步的生物学研究表明，“刚性棒”的长度与不同脂肪酸构建的人工膜的深度之间存在相关性。如果成功，这种方法将用于将dag -内酯转移到质膜上。4)合成的一种靶dag -内酯具有非常强的刺激α -分泌酶活性的活性，是治疗阿尔茨海默病的重要治疗手段。B.黄酮乙酸类似物。合成了一种具有叠氮基团的黄酮乙酸（FAA）的合成类似物，并证明其活性与母体FAA相同。叠氮化物部分将用于寻找负责FAA活性的分子靶标。DNA甲基转移酶项目（Zebularine）。在T24膀胱癌和其他肿瘤细胞系中，证明了zebularine 2(1H)-嘧啶核苷能够重新激活沉默的p16基因并使启动子区域去甲基化。为了克服2'-脱氧西蓝碱与DNA结合水平低的问题，合成了几种单磷酸前药。前两种药物的测试都失败了，更多的类似物正在开发中。Zebularine计划在今年年底前进入临床试验阶段。

A. Protein Kinase C ProjectThe universe of synthetic DAG-lactones designed as potent PKC ligands continues to expand with the objective of achieving full isozyme specificity. The major findings this year are: 1) Syntheses of additional 96-member libraries on a solid-phase support continue with the intent to maximally explore the chemical space surrounding the binding site at the protein-membrane interface. New chemical improvements in the synthesis and characterization of the library members by mass spectrometry continue to be made.2) The first specific DAG-lactone targeting a non-kinase protein containing a C1 domain was discovered. The compound binds with low nanomolar binding affinity to RasGRP while showing weak binding activity for the PK-C isozymes. The biological consequences of this selective binding are being explored. 3) The synthesis of DAG-lactones with a side chain in the form of a "rigid rod" constructed with alternating acetylene units and benzene rings was completed Preliminary biological studies indicate a correlation between length of the "rigid rod" and depth of artificial membranes built with different fatty acids. If successful, this approach will be used to translocate DAG-lactones exclusively to the plasma membrane.4) One of the target DAG-lactones synthesized showed very potent activity in stimulating alpha-secretase activity, which is an important therapeutic approach in the treatment of Alzheimer's disease. B. Flavone acetic acid analogues. A synthetic analogue of flavone acetic acid (FAA) with an azido group designed to function as a biological reported was synthesized and shown to be as active as parent FAA. The azide moiety will be used to find the molecular target responsible for the activity of FAA. C. DNA Methyl Transferase Project (Zebularine). The ability of zebularine 2(1H)-pyrimidinone riboside to reactivate a silenced p16 gene and demethylate the promoter region in the T24 bladder carcinoma and other tumor cell lines was demonstrated. Several monophosphate pro-drug of 2'-deoxyzebularine were synthesized in order to overcome the low level of incorporation into DNA. The first two pro-drugs tested failed, and more analogues are being explored. Zebularine is scheduled to enter clinical trials before the end of the year.