Pyrrolo pyridines, 4,5,6,7-tetrahydro

DaB bei dieser Cycloadditionsreaktion auch das Aiken nicht beliebig gewahlt werden kann, zeigt die Reaktion des Iminium-ylids mit l-Methyl-l,2,3,6-tetrahydro-pyridin, die nur in maBiger Ausbeute zu einem Gemisch von 2,5-Dimethyl-octahydro-(pyrrolo[3,4-c]pyridiny und 1,4-Dimethyl-piperazin fiihrt2 das letztere Produkt bildet sich auch in an-deren Fallen durch Cyclodimerisierung des Iminium-ylids. 

Reaction of l-(3,4-dimethoxybenzyl)-9-hydroxy-l,2,3,4-tetrahydro-8//-pyrido[l,2-a]pyrazin-8-one with 37% formaldehyde solution gave a tetracyclic tetrahydroprotoberberine analogue in a Mannich-type reaction (78AJC187). Reactions of 2,3,4,4a,5,6-hexahydro-l//-pyrazino[l,2-a]-quinolines with 1 W-pyrrolo[2,3-h]pyridine in the presence of 37% aqueous CH20 and AcONa in AcOH, and with 3-dimethylaminomethyl-l //-pyrrolo[2,3-h]pyridine afforded 3-[(l//-pyrrolo[2,3-h]pyridin-3-yl)methyl] derivatives (94MIP6 96USP5576319). 

Synthesis of 5-oxo-4,5,6,7-tetrahydro-l//-pyrrolo-[3,2-f>] pyridine-3-carboxyhc acids by three-component condensation of 3-aminopyrrole derivatives. 

NaNOa added to a soln. of methyl 2-aminomethyl-3-methoxycarbonylmethyl-5-methoxycarbonyl-4-pyrrolepropionate hydrochloride in glacial acetic acid, stirred 15 min., the precipitated salts removed, Ng passed 10 min. through the soln., porphobilinogen lactam methyl ester added, and heated 0.5 hr. at 90° methyl 2-(3 - methoxycarbonylmethyl - 4 -/ -methoxycarbonylethyl -5 -methoxycarbonyl -2 -pyrrylmethyl)-5-oxo-4,5,6,7-tetrahydro-lH-pyrrolo[2,3-c]pyridine-3-propionate. Y 73%. F. e. s. B. Frydman et al.. Am. Soc. 93, 2738 (1971). 

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