Synthesis of a DNA-cleaving bis(propargylic) sulfone crown ether
作者:Sean Michael Kerwin
DOI:10.1016/s0040-4039(00)79955-2
日期:1994.2
The prototypical bis(propargylic) sulfone crownether 5 was synthesized in six steps and 26 % overall yield from readily available starting materials. In alkaline aqueous buffer, compounds 5 cleaves supercoiled DNA.
Syntheses of Strychnine, Norfluorocurarine, Dehydrodesacetylretuline, and Valparicine Enabled by Intramolecular Cycloadditions of Zincke Aldehydes
作者:David B. C. Martin、Lucas Q. Nguyen、Christopher D. Vanderwal
DOI:10.1021/jo2020246
日期:2012.1.6
base-mediated intramolecular Diels–Alder cycloadditions of tryptamine-derived Zincke aldehydes is described. This important complexity-generating transformation provides the tetracyclic core of many indole monoterpene alkaloids in only three steps from commercially available starting materials and played a key role in short syntheses of norfluorocurarine (five steps), dehydrodesacetylretuline (six steps), valparicine
A two-step reaction sequence starting with the indium-mediatedallenylation of aldehydes with 4-bromo-2-butyn-1-ols and subsequent ozonolysis of the resulting allenylic product was developed to generate a variety of dihydroxyacetone derivatives. The regioselectivity of the indium-promoted C–C bond-forming reaction can be manipulated through hydroxy protecting groups on 4-bromo-2-butyn-1-ol, yielding
Derivatives of 2-methylenepenam: analogues of clavulanic acid
作者:Edward G. Brain、Nigel J. P. Broom、Roger I. Hickling
DOI:10.1039/p19810000892
日期:——
Some substituted 2-methylenepenams have been synthesised by ring closure of acetylenic azetidinone-thiols. Substituents on the methylene group include aryl, hydroxymethyl, and alkoxycarbonylvinyl.
1,2-Dibromotetrachloroethane: an efficient reagent for many transformations bymodified Appel reaction
作者:Selçuk EŞSİZ、Arif DAŞTAN
DOI:10.3906/kim-1804-41
日期:——
been developed for the synthesis of alkyl bromides from various alcohols under mild conditions using a triphenylphosphine (PPh$_3})$/1,2-dibromotetrachloroethane (DBTCE) complex in excellent yields and very short time (5 min). This method can also be applied for the transformation of chiral alcohols to their corresponding bromides in very high enantiomeric excess. The PPh$_3}$/DBTCE complex is also