Condensed pyrimidine systems. XIII. Some amino-substituted derivatives of guanine and 6-thioguanine was written by Elion, Gertrude B.;Lange, William H.;Hitchings, George H.. And the article was included in Journal of the American Chemical Society in 1956.Synthetic Route of C6H7N3O This article mentions the following:
Crude 4,5-diamino-6-hydroxy-2-mercaptopyrimidine (100 g.) refluxed 2 hrs. with 500 cc. 90% HCO2H, cooled, and filtered, the filter cake pressed dry, suspended in 200 cc. HCONH2, heated 2 hrs. at 175-85°, cooled, and filtered, and the crude product (100.5 g.) dissolved in 2 l. N NaOH, filtered, and reprecipitated with glacial AcOH gave 90 g. 6-hydroxy-2-mercaptopurine (I). I (42 g.) in 250 cc. 2N NaOH treated slowly with stirring with 31.5 g. Me2SO4 at 25-40°, the mixture stirred 1 hr., kept at room temperature overnight, adjusted to pH 5 with glacial AcOH and chilled, and the precipitate washed with cold H2O and dried at 110° gave 44 g. (98% pure) 6-hydroxy-2-methylthiopurine (II); it did not melt below 300°. II heated with 3-4 molar equivalents aliphatic amine 24 hrs. at 140° (48 hrs. at 160° with aromatic amines) in a sealed tube gave the corresponding 2-(substituted-amino)-6-hydroxypurines (IIa). The mixture with MeNH2 evaporated to dryness in vacuo, the solid residue dissolved at room temperature in about 5 volumes H2O and filtered, the filtrate adjusted with AcOH to pH 5, and the precipitate dissolved in 40 volume hot 0.3N HCl and reprecipitated with NH4OH (pH 6) gave 37% 2-methylamino-6-hydroxypurine (III). A similar run with 14% MeNH2 in MeOH gave a 65% yield. In the same manner was prepared the EtNH analog of III, in 30% yield from 33% aqueous EtNH2. The reaction mixture from Me2NH cooled, diluted with 3 volume MeOH, chilled, and filtered, and the residue recrystallized from 100 parts boiling H2O gave 50% 2-Me2N analog of III; in a run with 2 molar equivalents 12% Me2NH in MeOH the yield was 61%. The mixture from PhNH2 diluted with 20 volumes 1:1 absolute EtOH-Et2O precipitated 56% PhNH analog (IV) of III. In the same manner was prepared the p-Cl derivative of IV in 35% yield. The mixture from piperidine (without solvent) diluted with about 4 parts H2O, filtered, acidified to pH 5 with HCl, and filtered, the filtrate evaporated to dryness in vacuo, the residue treated with 50 parts 1:1 6N HCl-Me2CO to give the HCl salt of the product, the filter residue extracted several times with 10 parts boiling H2O, the extract chilled, filtered, and treated in the same manner, and the combined crude solid product recrystallized from 50 parts hot 6N HCl, treated with Darco, and diluted with an equal volume Me2CO and chilled gave 33% 2-piperidino-6-hydroxypurine (V). A similar run with piperidine in EtOH gave 10% V; a 19% yield of V was obtained in a run with 4 molar equivalents piperidine in 2 molar equivalents concentrated HCl. The appropriate 2-(substituted-amino)-6-hydroxypurine refluxed 3 hrs. with 5 parts freshly pulverized P2S5 and 50 parts dry pyridine, the pyridine removed in vacuo, the residue heated 15-20 min. with 40 volume H2O, cooled, diluted cautiously with an equal volume concentrated NH4OH, chilled, and filtered, and the filtrate concentrated to a small volume in vacuo, adjusted to pH 5, and chilled gave the corresponding 2-(substituted-amino)-6-mercaptopurine (VI) (substituted-amino group, mole crystal water, and % yield given): MeNH, 0.25, 64; EtNH, 0.5, 45; Me2N, 1, 52; PhNH, 1.5, 34; piperidino, 0.5, 51. The ultraviolet absorption maximum and min. of the IIa and VI at pH 1 and 11 are tabulated. In the experiment, the researchers used many compounds, for example, 3-Aminopicolinamide (cas: 50608-99-6Synthetic Route of C6H7N3O).
3-Aminopicolinamide (cas: 50608-99-6) belongs to amides. The amide group is called a peptide bond when it is part of the main chain of a protein, and an isopeptide bond when it occurs in a side chain, such as in the amino acids asparagine and glutamine. The presence of the amide group –C(=O)N– is generally easily established, at least in small molecules. It can be distinguished from nitro and cyano groups in IR spectra. Amides exhibit a moderately intense νCO band near 1650 cm−1. By 1H NMR spectroscopy, CONHR signals occur at low fields. In X-ray crystallography, the C(=O)N center together with the three immediately adjacent atoms characteristically define a plane.Synthetic Route of C6H7N3O
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics