4-AMINO-6-(HETEROCYCLIC)PICOLINATES AND 6-AMINO-2-(HETEROCYCLIC)PYRIMIDINE-4-CARBOXYLATES AND THEIR USE AS HERBICIDES
申请人:Dow AgroSciences, LLC
公开号:US20150126372A1
公开(公告)日:2015-05-07
4-Amino-6-(heterocyclic)picolinic acids and their derivatives; 6-amino-2-(heterocyclic)pyrimidine-4-carboxylates and their derivatives; and methods of using the same as herbicides.
4-amino-6-(heterocyclic)picolinates and 6-amino-2-(heterocyclic)pyrimidine-4-carboxylates and their use as herbicides
申请人:Dow AgroSciences, LLC
公开号:US09278985B2
公开(公告)日:2016-03-08
4-Amino-6-(heterocyclic)picolinic acids and their derivatives; 6-amino-2-(heterocyclic)pyrimidine-4-carboxylates and their derivatives; and methods of using the same as herbicides.
Radiosynthesis of 4-[ 18 F]fluoro- l -tryptophan by isotopic exchange on carbonyl-activated precursors
作者:Philipp S. Weiss、Johannes Ermert、Johnny Castillo Meleán、Dominique Schäfer、Heinz H. Coenen
DOI:10.1016/j.bmc.2015.06.073
日期:2015.9
Several F-18-labeled aromatic amino acids have been developed primarily for tumor imaging with positron-emission-tomography (PET). Also, F-18-labeled tryptophan derivatives were synthesized by electrophilic F-18-fluorination or by introducing a [F-18]fluoroalkyl group. Here, a 3-step method for a nucleophilic radiosynthesis of 4-[1(8F)]fluoro-L-tryptophan was developed. A carbonyl activated precursor containing a chiral amino acid building block was radiofluorinated by isotopic exchange, followed by removal of the activating formyl group by reductive decarbonylation and subsequent cleavage of the building block under acidic conditions. The title compound was obtained within 100 min with a radiochemical yield of about 13%, a molar activity of >70 MBq/mmol and an enantiomeric excess of >99%. (C) 2015 Elsevier Ltd. All rights reserved.
US20140274695A1
申请人:——
公开号:——
公开(公告)日:——
In Search of Simplicity and Flexibility: A Rational Access to Twelve Fluoroindolecarboxylic Acids
a basicity gradient-driven selective migration of the heavy halogen. An unexpected finding on the way to the target compds. were the rigorously site-selective metalation of the 5-fluoro-N-(trialkylsilyl)indole (exclusive deprotonation of the 4-position). The fluoroindoles, although previously known, were accessed more conveniently from suitably substituted nitrobenzenes using the Bartoli or the Leimgruber-Batcho