Expeditious N-monoalkylation of 1,4,7,10-tetraazacyclododecane (cyclen) via formamido protection
摘要:
The reaction of cyclen 1 with chloral hydrate afforded exclusively 1,4,7-triformylcyclen 2 in high yield; the triprotected macrocycle was easily alkylated with various electrophiles in good to excellent yields. The alkaline removal of the formyl groups provided a selective entry into N-monosubstituted cyclen derivatives. (C) 2000 Elsevier Science Ltd. All rights reserved.
ELECTROPHORESIS DISPERSION LIQUID, ELECTROPHORESIS SHEET, ELECTROPHORESIS DEVICE, AND ELECTRONIC APPARATUS
申请人:Seiko Epson Corporation
公开号:EP3081984A2
公开(公告)日:2016-10-19
An electrophoresis dispersion liquid includes first electrophoretic particle of a scattering system having an ionic group on a surface thereof; second electrophoretic particle of a coloring system having a polarization group on the surface thereof; and a dispersion medium. It is preferable that the ionic group is an acidic group, and further includes a ring structure that forms an acidic group and a salt. It is preferable that the polarization group is an organic group having a main skeleton, and a substituent bonded to the main skeleton.
Synthesis of Lipophilic Paramagnetic Contrast Agents
作者:William C. Baker、Michael J. Choi、Daniel C. Hill、Julie L. Thompson、Peter A. Petillo
DOI:10.1021/jo981920r
日期:1999.4.1
The facile, high-yielding synthesis of a series of macrocycles 7a-k in 75-100% yield is reported. The transformation of these compounds to their carboxymethylated analogues 8a-k in 75-90% yield and subsequent gadolinium complexes 9a-k provides a series of homologous neutral paramagnetic contrast agents (PCAs) with tunable lipophilicity. Alkylated cationic intermediates 6a-k are prepared in yields of 72-94% from glyoxal adduct of cyclen (5) and slight excesses of alkyl iodides. The methodology is selective for monoalkylation and amenable to large-scale synthesis.