Prodrugs of GABA analogs, compositions and uses thereof
申请人:Gallop A. Mark
公开号:US20060229361A1
公开(公告)日:2006-10-12
The present invention provides prodrugs of GABA analogs, pharmaceutical compositions of prodrugs of GABA analogs and methods for making prodrugs of GABA analogs. The present invention also provides methods for using prodrugs of GABA analogs and methods for using pharmaceutical compositions of prodrugs of GABA analogs for treating or preventing common diseases and/or disorders.
SENSITIVE OLIGONUCLEOTIDE SYNTHESIS USING SULFUR-BASED FUNCTIONS AS PROTECTING GROUPS AND LINKERS
申请人:Fang Shiyue
公开号:US20210032281A1
公开(公告)日:2021-02-04
Embodiments for the synthesis of sensitive oligonucleotides as well as insensitive oligonucleotides are provided. Sulfur-based groups are used for the protection of exo-amino groups of nucleobases, phosphate groups and 2′-OH groups, and as cleavable linker for linking oligonucleotides to a support. Oligonucleotide syntheses are achieved under typical conditions using phosphoramidite chemistry with important modifications. To prevent replacing sulfur-based protecting groups by acyl groups via cap-exchange, special capping agents are used. To retain hydrophobic tag to assist RP HPLC purification, special phosphoramidites are used in the last synthetic cycle. With the sulfur-based groups for protection and linking, oligonucleotide deprotection and cleavage are achieved via oxidation followed by beta-elimination under mild conditions. Therefore, besides for insensitive oligonucleotide synthesis, the embodiments of the invention are capable for the synthesis of oligonucleotide analogs containing sensitive functional groups that cannot survive the harsh conditions used in prior art oligonucleotide synthesis technologies.
Transdithioacetalization of acetals, ketals, oximes, enamines and tosylhydrazones catalysed by natural kaolinitic clay
作者:G. K. Jnaneshwara、N. B. Barhate、A. Sudalai、V. H. Deshpande、R. D. Wakharkar、A. S. Gajare、M. S. Shingare、R. Sukumar
DOI:10.1039/a706475f
日期:——
Natural kaolinitic clay efficiently catalyses the transdithioacetalization of acetals, ketals, oximes, enamines and tosylhydrazones with ethane-1,2-dithiol and propane-1,3-dithiol to produce the corresponding dithiolanes in high yields.
Entirely Solvent-Free Procedure for the Synthesis of Distillable 1,3-Dithianes Using Lithium Tetrafluoroborate as a Reusable Catalyst
作者:Tsuneo Sato、Kiyoshi Kazahaya、Shinya Tsuji
DOI:10.1055/s-2004-829084
日期:——
Treatment of various types of aldehydes and ketones with 1,3-propanedithiol in the presence of a catalytic amount of lithium tetrafluoroborate at 25 °C under solvent-free conditions followed by direct purification by distillation of the resulting mixture affords the corresponding 1,3-dithianes in good to excellent yields. Chemoselective protection of keto aldehydes is also successfully achieved over the catalyst. The catalyst can be recovered and reused.
Tandem Carbon−Carbon Bond Constructions via Catalyzed Cyanation/Brook Rearrangement/C-Acylation Reactions of Acylsilanes
作者:Xin Linghu、David A. Nicewicz、Jeffrey S. Johnson
DOI:10.1021/ol0263649
日期:2002.8.1
see text] A tandem nucleophile-catalyzed cyanation/Brookrearrangement/C-acylation has been developed. Phase transfer cocatalysts facilitate cyanide-catalyzed reactions between acylsilanes and cyanoformates to afford protected tertiary carbinol products. A catalytic cycle is proposed involving cyanation of an acylsilane, [1,2]-Brook rearrangement, and C-acylation of the derived carbanion by a cyanoformate