Synthesis and selected properties of N-substituted pyrrolo[2,1-c]-1,3-diazacycloalkano[1,2-a]pyrazinones

Abstract

Synthesis and selected properties of N substituted pyrrolo[2,1 c] 1,3 diazacycloalkano[1,2 a]pyrazinonesThe reactions of methyl α (2 formyl 1H pyrrol 1 yl)carboxylates with N substituted aliphatic 1,2 , 1,3 , and 1,4 diamines afford new pyrrole containing heterocyclic systems: 1,2,3,10b tetrahydroimidazo[1,2 a]pyrrolo[2,1 c]pyrazin 5(6H) ones, 1,3,4,11b tetrahydro 2H pyrrolo[2´,1´:3,4]pyrazino[1,2 a]pyrimidin 6(7H) ones, and 1,2,3,4,5,12b hexahydro pyrrolo[2´,1´:3,4]pyrazino[1,2 a][1,3]diazepin 7(8H) ones. The reduction of these compounds with different reagents was studied.* t 1 , 120-150 s; t 2 , 1 day; t 3 , 1 week. ** One isomer. Scheme 6R´ = Me, n = 1 (a); R´ = H, n = 2 (b) which was obtained by subtraction of the spectrum recorded within one week after the dissolution of crystalline compound 1j in CDCl 3 from the spectrum recorded immediately after the dissolution (CDCl 3 ), δ: 1.79 (d, H, H a (CH b )Ar, 2 J = 13.3 Hz); 2.77 (ddd, 1 H, H a C(2), 2 J 2a,2b = 12.0 Hz, 3 J 2a,3b = 11.4 Hz, 3 J 2a,3a = 8.7 Hz); 2.89 (ddd, 1 H, H b C(2), 2 J 2b,2a = 12.0 Hz, 3 J 2b,3b =8.0 Hz, 3 J 2b,3a = 2.1 Hz); 2.99 (d, 1 H, H b (CH a )Ar, 2 J = 13.3 Hz); 3.33 (ddd, 1 H, H a C(3), 2 J 3a,3b = 11.5 Hz, 3 J 3a,2a = 8.7 Hz, 3 J 3a,2b = 2.1 Hz); 3.47 (dd, 1 H, H a (CH b )Ph, 2 J = 14.0 Hz, 3 J = 4.2 Hz); 3.55 (ddd, 1 H, H b C(3), 2 J 3b,3a = = 11.5 Hz, 3 J 3b,2a = 11.4 Hz, 3 J 3b,2b = 8.0 Hz); 3.68 (dd, H b (CH a )Ph, 2 J = 14.0 Hz, 3 J = 4.2 Hz); 3.84 and 3.86 (both s, 3 H each, 2 OMe); 5.04 (t, 1 H, CHCH 2 Ph, 3 J = 4.2 Hz); 5.20 (s, 1 H, H(10b)); 6.21 (m, 1 H, H(10)); 6.39 (m, 1 H, H(9)); 6.54 (d, 1 H, H Ar (5), 3 J = 8.1 Hz); 6.67 (m, 1 H, H(8)); 6.74 (d, 1 H, H Ar (6), 3 J = 8.1 Hz); 6.90-7.11 (m, 6 H, Ph, H Ar (2)). The 1 H NMR spectrum of the second diastereomer of 1j, which was obtained by subtraction of the spectrum recorded immediately after the dissolution of crystalline compound 1j in CDCl 3 from the spectrum recorded within one week after the dissolution (CDCl 3 ), δ: 2.39 (ddd, 1 H, H a C(2), 2 J 2a,2b = 10.9 Hz, 3 J 2a,3b = 11.1 Hz, 3 J 2a,3a = 8.5 Hz); 3.05 (ddd, 1 H, H b C(2), 2 J 2b,2a = 10.9 Hz, 3 J 2b,3b =7.6 Hz, 3 J 2b,3a = 1.9 Hz); 3.22-3.39 (m, 4 H, CH 2 Ph, H a (CH b )Ar, H a C(3)); 3.59 (ddd, 1 H, H b C(3), 2

First Synthesis of 2,9-Disubstituted cis-2,3a,7b,9,10a,14b- Hexaazaperhydrodibenzotetracenes

“…On the basis of our results 1,6,7 and the literature data, [31][32][33] it can be assumed that the catalytic cycle of the reaction between cis-1,6,7,12-tetraazaperhydrotetracene and N,Ndi(methoxymethyl)alkylamine or 1,3,5-tricycloalkyl-1,3,5triazinane includes the step of coordination of the heteroatom with the metal catalyst. 33 This fact contributes to a shift of the electron density from the heteroatom to the metal ion and it leads to the formation of carbocations.…”

New Catalytic Method for the Synthesis of 2,7-Dicycloalkyl-hexaazaperhydropyrenes

“…The experimental results as well as published data suggest [20][21][22][23] that the ring transformation reaction of 1,3,5-tricycloalkyl-1,3,5-triazine with tetraazadecalin 1 represents a multistaged chemical process. It comprises the successive steps of coordination of the tertiary nitrogen atom to the catalyst central ion, ring opening of the starting heterocycle, nucleophilic addition of secondary amine to a carbocation, and subsequent intermolecular cyclization to give the target hexaazaperhydropyrenes (Scheme 2).…”

Ribose conversion with amino acids into pyrraline platform chemicals – expeditious synthesis of diverse pyrrole-fused alkaloid compounds

“…, 1,2-ethanediamine) can be utilized in lactam formation with pyrralines 5, where initially formed imine may react with the second amine by cyclization. 40,41 One of the resulting two symmetrical secondary amines participated in further cyclization with the ester group to form pyrrolo-piperazinones 7 with an imidazolidine ring as the third core in 58–94% yields ( Table 4 ). The conversion of pyrralines 5 with norephedrine was reported, 42 where the initially formed imine was reacted with the alcohol group by cyclization to form an oxazolidine unit, which underwent further cyclization with the ester group to produce pyrrolo-piperazinones with the oxazolidine unit.…”