the remaining (S)-substrate and the resulting (R)-alcohol was achieved by a simple procedure without any laborious column chromatography. The substrate was easily hydrolyzed with NaOH in MeOH―H 2 O to give the (S)-alcohol. This procedure was also applicable to the preparation of other optically active secondaryalcohols. As expected, an introduction of a hydrophobic spacer between the MPEG moiety and
公开了中等分子量聚(乙二醇)(PEG)-支持的碳酸酯的酶介导的对映选择性水解。代表性的水溶性底物是通过将 (±)-1-苯基乙醇通过碳酸酯接头固定在单甲氧基 PEG (MPEG, av. M w 5000) 或 PEG (av. M w 4600) 上来制备的。猪胰腺脂肪酶 (PPL) 在混合溶剂 (己烷/缓冲液 = 9/1) 中于 0°C 对映选择性催化水解聚合物支持的底物,以提供相应的旋光化合物。在该系统中,剩余的 (S)-底物和所得的 (R)-醇的分离是通过简单的程序实现的,无需任何费力的柱层析。底物很容易用 NaOH 在 MeOH-H 2 O 中水解,得到 (S)-醇。该程序也适用于其他光学活性仲醇的制备。正如预期的那样,在 MPEG 部分和碳酸酯接头之间引入疏水间隔物会影响反应性和对映选择性。o 取代产生的转化率低于 m 和 p 取代底物反应的转化率。虽然具有对苯乙基间隔基的底物以低转化率获得最佳
Optimization of Solid-Supported Glaser-Hay Reactions in the Microwave
作者:Jessica Lampkowski、Johnathan Maza、Sanjana Verma、Douglas Young
DOI:10.3390/molecules20045276
日期:——
The translation of organometallic reactions into a microwave reactor has numerous advantages. Herein, we describe the application of a previously developed solid-supported Glaser-Hay reaction to microwave conditions. Overall, an array of diynes has been prepared demonstrating the ability to conduct chemoselective reactions in the microwave within 20 min compared to the 16 h thermal conditions. Moreover
Application of the Solid-Supported Glaser–Hay Reaction to Natural Product Synthesis
作者:Jessica S. Lampkowski、Diya M. Uthappa、John F. Halonski、Johnathan C. Maza、Douglas D. Young
DOI:10.1021/acs.joc.6b02407
日期:2016.12.16
synthetic reaction for the preparation of polyynes; however, chemoselectivity issues have precluded its widespread utilization. Conducting the reaction on a solid-support provides a mechanism to alleviate the chemoselectivity issues and provide products in high purities and yields. Moreover, the polyyne core is a key component to several naturalproducts. Herein, we describe the application of a solid-supported
Solid-Phase Synthetic Strategy and Bioevaluation of a Labeled δ-Opioid Receptor Ligand Dmt-Tic-Lys for <i>In Vivo</i> Imaging
作者:Jatinder S. Josan、David L. Morse、Liping Xu、Maria Trissal、Brenda Baggett、Peg Davis、Josef Vagner、Robert J. Gillies、Victor J. Hruby
DOI:10.1021/ol900200k
日期:2009.6.18
A general solid-phase synthetic strategy is developed to prepare fluorescent and/or lanthanide-labeled derivatives of the delta-opioid receptor (delta OR) ligand H-Dmt-Tic-Lys(R)-OH. The high delta-OR affinity (K-i = 3 nM) and desirable in vivo characteristics of the Cy5 derivative 1 suggest its usefulness for structure-function studies and receptor localization and as a high-contrast noninvasive molecular marker for live imaging ex vivo or in vivo.