Covalent Modification of Cyclooxygenase-2 (COX-2) by 2-Acetoxyphenyl Alkyl Sulfides, a New Class of Selective COX-2 Inactivators
作者:Amit S. Kalgutkar、Kevin R. Kozak、Brenda C. Crews、G. Phillip Hochgesang、Lawrence J. Marnett
DOI:10.1021/jm980303s
日期:1998.11.1
hept-2-ynyl sulfide (70) (Science 1998, 280, 1268-1270). Compound 70 selectively inactivates COX-2 by acetylating the same serine residue that aspirin acetylates. This paper describes the extensive structure-activity relationship (SAR) studies on the initial lead compound 2-acetoxyphenyl methyl sulfide (36) that led to the discovery of 70. Extension of the S-alkyl chain in 36 with higher alkyl homologues
Synthesis and evaluation of [14C]-Labelled and fluorescent-Tagged paclitaxel derivatives as new biological probes
作者:Ch.Srinivasa Rao、Jao-Jia Chu、Rai-Shung Liu、Yiu-Kay Lai
DOI:10.1016/s0968-0896(98)00158-8
日期:1998.11
results in this report demonstrate that (a) the new paclitaxel derivatives 4, 9, 11 could be prepared with good yields starting from paclitaxel; (b) the [14C]acetylation step was found to be better by using [14C]acetic anhydride rather than [14C]sodium acetate; (c) the radiochemical purity of 4 was 96% and its specific activity was 48 mCi/mmol; (d) the cytotoxicity of 4 was close to that of paclitaxel
Sequence-specific cleavage of DNA by N-bromoacetyldistamycin. Product and kinetic analyses
作者:Brenda F. Baker、Peter B. Dervan
DOI:10.1021/ja00189a054
日期:1989.3
N-Bromoacetyldistamycin (BO) is a designed molecule with two structural domains with distinct functions: sequence specific binding to double helical DNA and cleavage of the DNA backbone. An electrophilic bromoacetyl group is appended to the amino end of the tripeptide from the natural product distamycin A. Footprinting studies reveal that N-bromoacetyldistamycin binds within minutes to a 167 base pair
N-溴乙酰双霉素 (BO) 是一种设计好的分子,具有两个具有不同功能的结构域:与双螺旋 DNA 的序列特异性结合和 DNA 主链的切割。亲电溴乙酰基团附加到来自天然产物多他霉素 A 的三肽的氨基末端。 足迹研究表明,N-溴乙酰双霉素在几分钟内与 167 个碱基对 (bp) 限制性片段结合,位于四个富含 A、T 的位点 5 个碱基对尺寸为 5'-TTTAA、GTTTA、AAATT 和 GAAAT-3'。在 37 °C 下反应 5 小时后,该 167 bp 限制性片段中 GTTTA 位点的单个腺嘌呤处发生切割,并遵循哌啶处理程序。BD 的共价连接发生在腺嘌呤的 N3。3-(乙酰基二霉素)腺嘌呤是 BD 与 15 碱基对寡核苷酸双链体 5'-CGGTAGTTTATCACA-3' 在 37 °C 下反应释放的产物。哌啶处理后切割位点的 3' 和 5' DNA 末端是磷酸基团。BD 对双链 DNA
10th international symposium on the synthesis and applications of isotopes and isotopically labelled compounds - poster presentations Session 19, Sunday, June 14 to Thursday, June 18, 2009
Synthesis of Heptaprenyl−Lipid IV to Analyze Peptidoglycan Glycosyltransferases
作者:Yi Zhang、Eric J. Fechter、Tsung-Shing Andrew Wang、Dianah Barrett、Suzanne Walker、Daniel E. Kahne
DOI:10.1021/ja069060g
日期:2007.3.1
tremendous potential as antibiotic targets, but the potential has not yet been realized. Mechanistic studies have been hampered by a lack of substrates to monitor enzymatic activity. We report here the totalsynthesis of heptaprenyl−Lipid IV and its use to study two different PGTs from E. coli. We show that one PGT can couple Lipid IV to itself whereas the other can only couple Lipid IV to Lipid II. These
细菌被包含肽聚糖层的细胞壁包围,肽聚糖的完整性对于细菌的生存至关重要。在肽聚糖生物合成的最后阶段,肽聚糖糖基转移酶 (PGTs;也称为转糖基酶) 催化脂质 II 聚合形成线性聚糖链。PGTs 作为抗生素靶点具有巨大的潜力,但其潜力尚未实现。由于缺乏监测酶活性的底物,机制研究受到阻碍。我们在此报告了庚烯基-脂质 IV 的全合成及其用于研究来自大肠杆菌的两种不同 PGT。我们表明一个 PGT 可以将脂质 IV 与其自身结合,而另一个只能将脂质 IV 与脂质 II 结合。