The structure of ervinceine
UV spectrum: Xma x (ethanol) 248, 328 m/l (log ~ 4.12, 4.26), which is characteristic for a -methylene indol ine alkaloids. The NMR spectrum of ervinceine with signals at 8 8, 88 (NH, singlet), 6 .14-6 .91 (aromatic protons, 3H), [ 3.69 (singlet, COOCHs), 3.66 (singlet, OCHs), and 0.58 (triplet, --C--C~Hs). I The reduction of ervinceine with zinc in methanoiic sulfuric acid gave dihydroervinceine, C2zHz0NzOz, mp 118:119" C (methanol), [a]~3 +3.3 (c 0.9; chloroform). Its IR spectrum; Xrnax (ethanol) 249, 305 mg (log ~ 3.78, 3.73) is characteristic of ind0tine bases. Its mass spectrum has the molecular peak M + 370 (16%) and also peaks of ions with m/e 339 (M--OCH~) + I0%, 2~4 (M--86) + 26% and 124 (I00%).
Action of alkaline solutions of hydroxamic acids on guanylic acid and RNA
ConclusionsIt has been shown that at pH 10 and 37° C, hydroxamine acids do not react directly with any of the components of ribonucleic acid. Under these conditions the cleavage of the polynucleotide chain takes place at an appreciable rate.
One-pot synthesis of annulated pyrido[2,3-d:6,5-d]dipyrimidine derivatives using nitrogen based DBU catalyst in aqueous ethanol medium
Abstract We have reported DBU as an efficient organocatalyst for one-pot three-component synthesis of annulated pyrido[2,3- d :6,5- d ]dipyrimidine derivatives using aromatic aldehyde, thio-barbituric acid and 6-amino-uracil in aqueous ethanol under reflux. The attractive advantages of this process are mild reaction conditions, environment friendly procedure, short reaction times, easy isolation of products, and excellent yields (72–89%).