Structural Revision of (+)-Uprolide F Diacetate Confirmed by Asymmetric Total Synthesis
作者:Liangyu Zhu、Rongbiao Tong
DOI:10.1021/acs.orglett.5b00700
日期:2015.4.17
A new structure for the cytotoxic cembranolide uprolide F diacetate (UFD) was proposed, and an enantioselective totalsynthesis was accomplished to confirm that our revised structure correctly represented the natural UFD and its absolute configuration. Our synthesis features a late-stage, highly efficient, and diastereoselective Nozaki–Hiyama–Kishi macrocyclization (95% yield) and an unexpected reagent-controlled
Diastereo- and enantioselective preparation of β-alkylhomoallylic alcohols
作者:Yuichi Kobayashi、Yasunori Kitano、Yoshiyuki Takeda、Fumie Sato
DOI:10.1016/s0040-4020(01)90583-6
日期:1986.1
A new and efficient method for the preparation of four possible stereoisomers of β-alkylhomoallylic alcohols 1 has been developed which is based on the diastereoselective addition of nucleophiles to opticallyactive α-alkyl-β-trimethylsilyl-β,γ-unsaturated carbonyl compounds. The utility of this reaction is demonstrated by the synthesis of naturally occurring serricornin and corynomycolic acid.
does not cohere with the conventional logic of metathesis, according to which macrocycles are best closed at a disubstituted olefinic site; rather, the trisubstituted C11−C12 alkene flanked by an allylic ‐OH group served as the pivot point for synthesis. This motif was attained in good yield and excellent selectivity by a sequence of alkyne metathesis, trans‐hydrostannation and cross coupling. Because
Regioselective ring opening of chiral epoxyalcohols by primary amines
作者:Marc Canas、Marta Poch、Xavier Verdaguer、Albert Moyano、Miquel A. Pericàs、Antoni Riera
DOI:10.1016/0040-4039(91)80447-e
日期:1991.11
A reinvestigation of the titanium(IV)-mediated reaction of primary amines with chiral 2,3-epoxyalcohols shows that, contrary to previous reports, this reaction constitutes a general and practical process for the enantioselective synthesis of 3-amino-1,2-diols.
Sensing Remote Chirality: Stereochemical Determination of β-, γ-, and δ-Chiral Carboxylic Acids
作者:Marina Tanasova、Mercy Anyika、Babak Borhan
DOI:10.1002/anie.201410371
日期:2015.3.27
nonfunctionalizable stereocenters is a challenging task. Presented is a solution in which appropriately substituted bis(porphyrin) tweezers are used. Complexation of a suitably derivatized β‐, γ‐, or δ‐chiralcarboxylicacid to the tweezer induces a predictable helicity of the bis(porphyrin), which is detected as a bisignate Cotton Effect (ECCD). The sign of the ECCD curve is correlated with the absolute