Determination of the absolute stereochemistry of Etzionin
摘要:
The absolute configuration of Etzionin, a marine peptide-like compound isolated in 1989 from a red tunicate collected from the Red Sea has been determined by a combination of synthetic and spectroscopic procedures. Finally, its absolute stereochemistry has been established as 3S,3'R. (C) 2003 Elsevier Science Ltd. All rights reserved.
In 2-(2-alkenoyloxy)-5-alkoxytropones, showing a monotropic smectic A phase, the introduction of a double bond lowers the melting and clearing points as well as the recrystallization temperatures.
在显示单向近晶 A 相的 2-(2-烯酰氧基)-5-烷氧基托酮中,双键的引入降低了熔点和清光点以及重结晶温度。
Development of a simple system for the oxidation of electron-rich diazo compounds to ketones
作者:Nicholas R. O’Connor、Peter Bolgar、Brian M. Stoltz
DOI:10.1016/j.tetlet.2016.01.020
日期:2016.2
Mild heating of diazo compounds in DMSO furnishes ketone products in moderate to excellent yields. The reaction is particularly effective on electron-rich substrates and exhibits high chemoselectivity, allowing for the use of diazo compounds containing additional oxidation-prone functional groups. This straightforward protocol offers an alternate route to synthetically useful α-ketoesters from readily
α,β-Unsaturated esters are formed in good yields when aldehydes are heated with orthoacetates in the presence of a catalytic amount of phenol.
当醛在催化量的苯酚存在下与原乙酸酯一起加热时,会以高收率形成α,β-不饱和酯。
Total Synthesis of TK-57-164A, Isariotin F, and Their Putative Progenitor Isariotin E
作者:Jacob Y. Cha、Yaodong Huang、Thomas R. R. Pettus
DOI:10.1002/anie.200904716
日期:2009.12.7
Keeping it simple: A simple strategy for the totalsynthesis of three complex natural products has been developed, while also confirming the putative generation of 1 and 2 from 3. The benefits of a simple dissymmetric 2,5‐cyclohexadienone are illustrated and provide the foundation for rapid diastereoselective functionalization leading to the first totalsynthesis of these compounds.
Reactions de wittig, wittig-horner et knoevenagel par activation anionique avec l'alumine ou le fluorure de potassium depose sur l'alumine, sans solvant