1,2‐Dihydro‐1‐hydroxy‐2,3,1‐benzodiazaborine Bearing an Acridine Moiety as a Circular Dichroism Probe for Determination of Absolute Configuration of Mono‐Alcohols
A new chiral probe molecule for mono‐alcohols is developed by using 1,2‐dihydro‐1‐hydroxy‐2,3,1‐benzodiazaborine (DAB) bearing an acridine moiety 1. In the presence of mono‐alcohols, DAB 1 forms borate 2 by boronic ester formation, followed by coordination of the acridine moiety to the boron atom. Borate 2 has a chiral center on the boron atom and works as a stereodynamic circular dichroism (CD) probe
(<i>R</i>)- and (<i>S</i>)-4-TIPS-3-butyn-2-ol. Useful Precursors of Chiral Allenylzinc and Indium Reagents
作者:James A. Marshall、Patrick Eidam、Hilary Schenck Eidam
DOI:10.1021/jo060542k
日期:2006.6.1
purity by reduction of the ynone precursor 4 with the Noyori N-tosyl-1,2-diphenylethylenediamineruthenium cymene catalyst is described. The mesylate derivative of the (S) enantiomer (1c) is converted in situ to an allenylzinc or indium reagent in the presence of a catalyst derived from Pd(OAc)2 and Ph3P and either Et2Zn or InI. A second in situ addition of these reagents to aldehydes leads to anti homopropargylic
Total Synthesis of Sarpagine-Related Bioactive Indole Alkaloids
作者:M. Toufiqur Rahman、Jeffrey R. Deschamps、Gregory H. Imler、James M. Cook
DOI:10.1002/chem.201705575
日期:2018.2.16
tryptophan derivatives resulted in an improved stereospecific access to the key bicyclo[3.3.1]nonane core of bioactive C‐19 methyl substituted sarpagine/macroline/ajmaline indole alkaloids with excellent diastereoselectivity by internal asymmetric induction. Complete stereocontrol of the C‐19 methyl function in either the α‐ or β‐configuration was achieved, which enables the totalsynthesis of any member
Regiospecific, Enantiospecific Total Synthesis of C-19 Methyl Substituted Sarpagine Alkaloids Dihydroperaksine-17-al and Dihydroperaksine
作者:Rahul V. Edwankar、Chitra R. Edwankar、Jeffrey Deschamps、James M. Cook
DOI:10.1021/ol202101p
日期:2011.10.7
The optically active tetracyclic ketone 8 was converted into the pentacylic core 14 of the C-19 methyl substituted Na-H sarpagine and ajmaline alkaloids via a critical haloboration reaction. The ketone 14 was then employed in the totalsynthesis of 19(S),20(R)-dihydroperaksine-17-al (1) and 19(S),20(R)-dihydroperaksine (2). The key regioselective hydroboration and controlled oxidation–epimerization
通过关键的卤硼化反应,光学活性四环酮8被转化为C-19甲基取代的Na - H沙帕津和阿马林生物碱的五环核14 。然后将酮14用于19( S ),20( R )-二氢帕拉克辛-17-al( 1 )和19( S ),20( R )-二氢帕拉克辛( 2 )的全合成。该方法中开发的关键区域选择性硼氢化和受控氧化-差向异构序列应提供一种通用方法来功能化阿马林相关吲哚生物碱中的 C(20)-C(21) 双键。
作者:Linlin Ding、Yue Zhao、Hongjian Lu、Zhuangzhi Shi、Minyan Wang
DOI:10.1002/anie.202313655
日期:2024.1.2
enantioselective propargyl-aryl cross-coupling between two electrophiles was achieved for the first time in a stereoconvergent manner. The potential utility of this conversion is demonstrated in the facile construction of stereoenriched bioactive molecule derivatives and medicinal compounds based on the diversity of acetylenic chemistry. Detailed experimental studies have revealed the key mechanistic features of this