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131.
Peter Wipf Stefan Werner Grace H.C. Woo Corey R.J. Stephenson Maciej A.A. Walczak Claire M. Coleman Leslie A. Twining 《Tetrahedron》2005,61(48):11488-11500
The multi-component condensation of organozirconocene, aldimine and zinc carbenoid was applied to the stereoselective synthesis of cyclopropane amino acid derivatives. These compounds served as scaffolds for the preparation of a 46-member library. The C- and N-termini of the cyclopropane amino acid derivatives were diversified by condensations with ten amines and ten acylating agents, respectively. To improve yields and accelerate library synthesis, most products were prepared under microwave irradiation and purified by polymer-bound scavengers and SPE methodology. All compounds were analyzed by LC-MS and a representative selection was fully characterized. 相似文献
132.
Shiro Komba 《Tetrahedron letters》2004,45(13):2759-2762
A new hydroxy protecting group for convenient preparation of oligosaccharide was developed using uni-chemo protection (UCP) concept. The UCP group was comprised of polymerized amino acid derivatives and protecting each hydroxyl groups by ester linkage. Depending on the polymerization degree, the hydroxyl groups were characterized and controlled. Using this protecting group, two kinds of sialyl-T analogues were successfully synthesized from same sugar parts merely by repeating Edman degradation and coupling. 相似文献
133.
Hideaki Hioki Yumiko Ohnishi Miwa Kubo Emi Nashimoto Yukinori Kinoshita Miho Samejima Mitsuaki Kodama 《Tetrahedron letters》2004,45(3):561-564
A fluorescence-labeled calix[4]arene library substituted with peptides at the upper rim was synthesized. Screening of the library for binding a dye-labeled oligopeptide indicated that some peptidocalix[4]arenes selectively bind the oligopeptide. The chemosensitivity of the library members for a target peptide was also investigated. 相似文献
134.
张力立 《科技情报开发与经济》1998,8(3):29-30
分析了图书馆在科技信息日益增多环境下的馆藏书刊如何进行适时合理调整,以适应新形势的新要求,更好地为科研工作服务 相似文献
135.
136.
Miwa Kubo 《Tetrahedron letters》2006,47(12):1927-1931
We synthesized a peptidocalix[4]arene library consisting of 1000 members that was suitable for peptide recognition in aqueous media. Some peptidocalix[4]arenes in the library were host molecules for guest peptides. Electrostatic interaction between the host and guest molecules was the most important factor for binding in aqueous media. 相似文献
137.
P.V. Pogodin A.A. Lagunin D.A. Filimonov M.C. Nicklaus V.V. Poroikov 《SAR and QSAR in environmental research》2019,30(10):759-773
ABSTRACTExisting data on structures and biological activities are limited and distributed unevenly across distinct molecular targets and chemical compounds. The question arises if these data represent an unbiased sample of the general population of chemical-biological interactions. To answer this question, we analyzed ChEMBL data for 87,583 molecules tested against 919 protein targets using supervised and unsupervised approaches. Hierarchical clustering of the Murcko frameworks generated using Chemistry Development Toolkit showed that the available data form a big diffuse cloud without apparent structure. In contrast hereto, PASS-based classifiers allowed prediction whether the compound had been tested against the particular molecular target, despite whether it was active or not. Thus, one may conclude that the selection of chemical compounds for testing against specific targets is biased, probably due to the influence of prior knowledge. We assessed the possibility to improve (Q)SAR predictions using this fact: PASS prediction of the interaction with the particular target for compounds predicted as tested against the target has significantly higher accuracy than for those predicted as untested (average ROC AUC are about 0.87 and 0.75, respectively). Thus, considering the existing bias in the data of the training set may increase the performance of virtual screening. 相似文献
138.
A very large diversity space of synthetically accessible compounds for use with drug design programs
Nikitin S Zaitseva N Demina O Solovieva V Mazin E Mikhalev S Smolov M Rubinov A Vlasov P Lepikhin D Khachko D Fokin V Queen C Zosimov V 《Journal of computer-aided molecular design》2005,19(1):47-63
We have constructed a very large virtual diversity space containing more than 1013 chemical compounds. The diversity space is built from about 400 combinatorial libraries, which have been expanded by choosing sizeable collections of suitable R-groups that can be attached to each link point of their scaffolds. These R-group collections have been created by selecting reagents that have drug-like properties from catalogs of available chemicals. As members of known combinatorial libraries, the compounds in the diversity space are in general synthetically accessible and useful as potential drug leads. Hence, the diversity space can be used as a vast source of compounds by a de novo drug design program. For example, we have used such a program to generate inhibitors of HIV integrase enzyme that exhibited activity in the micromolar range. 相似文献
139.
ShuXiaCAO JianChenZHANG MingYuNIU KuiLU XinChengLIAO YuFenZHAO 《中国化学快报》2004,15(6):652-654
N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ionization mass spectrometry (ESI-MS) was used to monitor the reaction. 相似文献
140.
Cristina Chamorro 《Tetrahedron》2004,60(39):8691-8697
A large and diverse library of a TAC-based tripodal synthetic receptor library (6) has been prepared by split-mix synthesis on the solid phase. Each receptor of the 46,656-member TAC-based library (6) is attached to a solid support bead and contains three different dipeptide arms. On-bead screening for binding of a d-Ala-d-Ala containing ligand (7) by the TAC-based library (6) was performed in phosphate buffer (0.2 N, pH=7.0). Remarkable selectivity for particular library members was observed. The best binding members from the screening were manually selected using fluorescence microscopy and subjected to structural analysis by sequencing. The thus determined binding sequences showed a high consensus. 相似文献