valuable in biomedical applications, their synthesis remains a long-standing challenge. To this end, a peptide-based strategy for such M-PEGs was developed. With macrocyclic sulfates as the key intermediates, a panel of oligoethylene glycol (OEG) containing ω-amino acids were prepared with high efficiency. Through solid phase peptidesynthesis (SPPS), these amino acids were conveniently assembled into a series
Camptothecin, which represents a class of natural products with high anticancer activity, suffers low water solubility which hampers its clinic application. To address this issue, monodisperse polyethylene glycols were employed to modify this class of natural products, including Camptothecin, 10-Hydroxycamptothecin, and SN38. Through selective modification with a series of monodisperse polyethylene
Chemo- and Regioselective Functionalization of Polyols through Catalytic C(sp<sup>3</sup>)–C(sp<sup>3</sup>) Kumada-Type Coupling of Cyclic Sulfate Esters
作者:Rodrigo Ramírez-Contreras、Bill Morandi
DOI:10.1021/acs.orglett.6b01745
日期:2016.8.5
This contribution describes a copper-catalyzed, C(sp3)–C(sp3) cross-coupling reaction of cyclic sulfate esters, a distinct class of electrophilic derivatives of polyols, with alkyl Grignard reagents to afford functionalized alcohol products in good yields. The method is operationally simple and highlights the potential of cyclic sulfate esters as highly reactive substrates in catalytic, chemoselective
oligoethylene glycols, especially hetero-functionalization, provides a series of highly valuable intermediates for life and materials sciences. However, the existing methods for the preparation of these compounds suffer excessive protecting and activating group manipulation as well as tedious purification. Here, a one-pot dual-substitution strategy with macrocyclic sulfates of polyethyleneglycols as the