Primary amides were easily prepared in 22–99% yields from the corresponding carboxylic acids 1 or 5 with NH4Cl via activation with ClCO2Et and Et3N. The enantiomers of the corresponding primary ami...
Reduction of Symmetric and Mixed Anhydrides of Carboxylic Acids by Sodium Borohydride with Dropwise Addition of Methanol
作者:Kenso Soai、Shuji Yokoyama、Katsuko Mochida
DOI:10.1055/s-1987-28035
日期:——
Symmetric and mixed anhydrides of carboxylic acids are reduced in high yields with sodium borohydride in tetrahydrofuran with dropwise addition of methanol.
Two series of sulfonylureasderivatives including 24 compounds ( 4 , 7 , 5a – 5o , 8a – 8h ), among them 17 newderivatives, have been synthesized and evaluated for their α -glucosidase inhibitory activity. Compounds 5c , 5h and 8e showed significant in vitro α -glucosidase inhibition with IC 50 values of 5.58, 79.85 and 213.36 µ m , respectively, comparing with the standard compounds acarbose (IC
Cobalt-Catalyzed, Aminoquinoline-Directed C(sp<sup>2</sup>)H Bond Alkenylation by Alkynes
作者:Liene Grigorjeva、Olafs Daugulis
DOI:10.1002/anie.201404579
日期:2014.9.15
A method for cobalt‐catalyzed, aminoquinoline‐ and picolinamide‐directed C(sp2)Hbondalkenylation by alkynes was developed. The method shows excellent functional‐group tolerance and both internal and terminal alkynes are competent substrates for the coupling. The reaction employs a Co(OAc)2⋅4 H2O catalyst, Mn(OAc)2 co‐catalyst, and oxygen (from air) as a terminal oxidant.
开发了一种钴催化、氨基喹啉和吡啶酰胺引导的炔烃 C(sp 2 ) H 键烯基化方法。该方法显示出优异的官能团耐受性,内部和末端炔烃都是偶联的有效底物。该反应采用Co(OAc) 2 ⋅4 H 2 O催化剂、Mn(OAc) 2助催化剂和氧气(来自空气)作为终端氧化剂。
Screening and Engineering the Synthetic Potential of Carboxylating Reductases from Central Metabolism and Polyketide Biosynthesis
作者:Dominik M. Peter、Lennart Schada von Borzyskowski、Patrick Kiefer、Philipp Christen、Julia A. Vorholt、Tobias J. Erb
DOI:10.1002/anie.201505282
日期:2015.11.2
Carboxylating enoyl‐thioester reductases (ECRs) are a recently discovered class of enzymes. They catalyze the highly efficient addition of CO2 to the double bond of α,β‐unsaturated CoA‐thioesters and serve two biological functions. In primary metabolism of many bacteria they produce ethylmalonyl‐CoA during assimilation of the central metabolite acetyl‐CoA. In secondary metabolism they provide distinct