DIRECT SYNTHESIS OF PROTECTED THIOLS BY TRIBUTYLSTANNYL GROUP
作者:Yoshio Ueno、Mamoru Nozomi、Makoto Okawara
DOI:10.1246/cl.1982.1199
日期:1982.8.5
Organic thiocyanates react with tributyltin hydride under homolytic conditions to give thiostannanes (Bu3Sn–SR), which are air-stable and high boiling protected forms of the parent thiols.
Synthesis of kanamycin a analogs containing 6-amino-3-oxa-2,3,4,6-tetradeoxy-d- and -l-glycero-hexopyranose
作者:Ryuji Kuwahara、Tsutomu Tsuchiya
DOI:10.1016/0008-6215(96)00051-1
日期:1996.6
6-Azido-3-oxa-2,3,4,6-tetradeoxy-D- and -L-glycero-hexopyranoses were synthesized in five steps from (2S)-and (2R)-1,2-O-isopropylideneglycerols, respectively. After conversion into the corresponding ethyl 1-thioglycosides, each was condensed with a protected derivative of 6-O-(3-amino-3-deoxy-alpha-D-glucopyranosyl)-2-deoxystreptamine (16). Deprotection and reduction of the azido group of the condensation
An umpolung N-alkylation reaction of α-cyclopropyl α-iminothioesters with diethylaluminum chloride or ethylmagnesiumbromide affords the corresponding N-ethylated α-aminothioesters in good yields. Subsequent oxidation and reaction of the N-ethylated product with a thiolate or a chloride anion proceed effectively to give the ring-opened products in good yields. In contrast, relatively “hard” nucleophiles
Exchange reactions between oxygen and sulphur derivatives of silicon, germanium, tin and lead
作者:D.A. Armitage、A.W. Sinden
DOI:10.1016/s0022-328x(00)88121-8
日期:1975.5
The exchange of oxygen functional groups ( OR, O and OCOMe) and sulphur functional groups ( SR, S ) between R3M (M = Si, Ge, Sn and Pb) and R2M (M = Si, Sn) shows, in general, the heavier Group IV element to prefer sulphur. This supports the phenomenological rationalisation that the softness of the organometallic residue increase with the atomic weight of M, though germanium probably resembles
R 3 M(M = Si,Ge,Sn和Pb)和R 2 M(M (Si,Sn)表示通常较重的IV族元素偏爱硫。这支持了现象学上的合理化,即有机金属残基的柔软度会随着M的原子量而增加,尽管锗的行为可能比硅更像硅,但它可能与锡相似。
Cinnoline Compounds as Inhibitors of Phosphodiesterase Type IV (Pde4)
申请人:Aston Nicola Mary
公开号:US20080280911A1
公开(公告)日:2008-11-13
There are provided according to the invention novel compounds of formula (I)