Synthese von 7‐unsubstituierten 7H‐Pyrrolo[2,3‐d]‐pyrimidinen

Abstract

Die Titelverbindungen 4 werden durch N‐7‐Dealkylierung der 2‐Furanylmethyl‐, 2‐Thiophenylmethyl‐, oder 1‐Phenylethyl‐Gruppe aus den Derivaten 2a – g und 10a – j mit Polyphosphoräure erhalten. Im Gegensatz zur 2‐Furanylmethyl‐Gruppe lassen sich die 2‐Thiophenylmethyl‐ und 1‐Phenylethyl‐Gruppen unabhängig von der Substitution am Heterobicyclus entfernen.

Chiral Pyrrolo[2,3-d]pyrimidine and Pyrimido[4,5-b]indole Derivatives: Structure−Activity Relationships of Potent, Highly Stereoselective A1-Adenosine Receptor Antagonists,

“…Compound 2 was obtained in analogy to compounds 19-21 (see below; Scheme 2) in a one-pot reaction of 3-hydroxy-2-butanone, 1-phenylethylamine, and malonodinitrile. [11][12][13][14] Pyrrolo[2, 3-d]pyrimidin-4-one derivatives 13 and 14 were prepared by condensation of 2 with benzoyl chloride or p-chlorobenzoyl chloride, respectively. N7,N 4 -Disubstituted pyrrolo[2,3-d]pyrimidines 10a,b were synthesized from 2a,b in three steps: Ring closure of 2 with formic acid yielded 9 which was treated with POCl 3 to afford the corresponding 4-chloro derivative.…”

“…7-Unsubstituted N 4 -substituted pyrrolo[2,3-d]pyrimidine 17, an isomer of 1a, was prepared from compound 13. Dealkylation in the 7-position by heating with polyphosphoric acid 13 to 15 and subsequent reaction with POCl 3 yielded 16. Substitution with a 10-fold excess of (R)-or (S)-1-phenylethylamine afforded 17, requiring a reaction time of several days.…”

Synthesis of Substituted Phenyl2-Aminopyridine-3-sulfonates

“…Treatment of imidate/ketene-O,N-acetal mixtures 7a and 7b respectively with (±)-1-phenylethylamine (14) in ethanol at room temperature afforded the primary/secondary ketene aminal 15, whose existence in the E-configuration was established by NOE-measurements (Scheme 4). Scheme 5 shows that cyclocondensation of ketene aminal 15 with phenylpropinal (11), acetylacetone (12) and trimethinium salt 13 in boiling ethanol-acetic acid yielded N-(1-phenylethyl)-substituted phenyl 2-aminopyridine-3sulfonates 16a-c. A planned deprotection of the 1-phenylethylgroup in 16a-c was managed by treatment with polyphosphoric acid at 60 °C [12][13][14] yielding pyridines 3a,j,k ( Table 2). Phenyl carbamoylmethanesulfonate (6) was prepared based upon the method described by Hinman et al 11 The syntheses of b-aminovinylketones were carried out according to a literature method.…”

Synthesis and -characterization of new N-substituted 2-aminopyrrole derivatives

“…This is due to the fact that aminopyrrols and their derivatives are unstable compounds. [3][4][5][6][7] 3-Aminopyrroles are more stable compounds compare with 2aminopyrroles. 8 There are two general methods known in the literature for the synthesis of 2aminopyrrole and its derivatives.…”