s-Triazolo[1,5-a]pyrimidine nucleosides. Site of N-glycosylation studies and the synthesis of an N-bridgehead guanosine analog

Abstract

Anionic micelles of sodium lauryl sulfate, NaLS, catalyze the reaction of the tri-p-anisylmethyl cation, R+, with butyl-and hexylamines and with 2-methylpyrrolidine. The catalysis increases with increasing length of the alkyl group of the amine, but is decreased by its branching. Cationic micelles of cetyltrimethylammonium bromide, CTABr, have little effect on the reaction rate, but nonionic micelles of Igepal are feebly catalytic.

Cyanoethylation of the salts of cyanoguanidine in aprotic solvents

“…This excludes from further considerations two of four possible tautomeric forms, and the choice between the other two, the cyanoimino 6a and the cyanoamino form 6b may also be made tentatively by means of its ir spectrum. The former appears to be the more likely, based on the observed low frequency of a high intensity band at 2165cm" 1 due to the -NG=N grouping as compared with an expected higher frequency of the-NHC N group, reinforced by a cross-conjugation in 6b (10,11). The uv spectra of 4 and 6 are consistent with structures 4a and 6a in that a strong absorption at ca.…”

A new approach to the synthesis of lamotrigine and other 3,5-diamino-1,2,4-triazine derivatives

“…16 3.043 N(8) (-x, -y, -z + 1) N(9)-H b (9) 0.888 2.290 155.60 3.120 N(1) (x, -y + 1/2, z + 1/2) Table 3. Selected bond lengths (d) and bond angles (ω) in compounds 6g…”

The synthesis of 8-aza-3-deazaguanosine [6-amino-1-(β-D-ribofuranosyl)-υ-triazolo[4,5-c]pyridin-4-one] via a novel 1,3-dipolar cycloaddition reaction

“…The filtrates were combined and concentrated in uacuo to yield a light yellow colored foam (18, 26.1 g, 87%) (one spot, tlc, SSA). A small sample (0.5g) was (18,8.15 g, 13.5 mmol) was dissolved in 18 mL of methylene chloride, the solution was cooled to -5WC, and the flask and contents weighed. Liquid (34) hydrogen cyanide was added (ca.…”

“…Research activity in this area has resulted in the synthesis of 8-azaguanine (2) (la), 8-azaguanosine (3, 4) (lb), and 2'-deoxy-8-azaguanosine (4); 3-deazaguanine (5) and 3-deazaguanosine (5); 1-deazaguanosine (6); 1-'Author to whom correspondence may be addressed. deaza-8-azaguanosine (7), and several (8,9) guanosine analogs containing a bridgehead nitrogen.…”