The structure of a new cranberry alkaloid, 12-methyl-1,2,3,4,6,7,12,12b-octahydroindolo[2,3-a]quinolizine was established using mass spectroscopy and by synthesis.

The phthalideisoquinoline system has been synthesized from substituted 2-phenyl-1,3-indandiones as starting materials. The key step in the synthesis is the rearrangement of the spirobenzylisoquinoline ring system to the phthalideisoquinoline system. The diastereomeric cordrastines, I and 11, have been synthesized by this method and their relative configurations have been established by comparison of their p.m.r. spectra with those of phthalideisoquinoline alkaloids of known configuration.Le systeme phtalideisoquinolCine a kt6 synthCtisC a partir des phCny1-2 indanediones-1,3 substituCes comme composCs de dCpart. L'Ctape cle dans la synthese correspond au rearrangement du svsteme cyclique spirobenzylisoquinolCine en systeme phtalidCisoquinolCine. Les cordrastines diastCrCoisomitres I et I1 ont CtC synthetisees par cette mCthode et leurs configurations relatives Ctablies par comparaison des spectres r.m.n. avec ceux d'alcaloides phtalideisoquinoltine de configuration connue.[Traduit par le journal]Can.

The syntheses of a variety of 3,4-disubstituted pyrroles including the antimitotic agent Verrucarin E are described. 3,4-Pyrroledicarboxylic esters were prepared through a Diels–Alder reaction. Partial hydrolysis of the diesters gave the 4-ester-3-acids which were modified to achieve the synthesis of a variety of unsymmetrically 3,4-disubstituted pyrroles. Raney nickel reduction of a thiolester gave hydroxymethyl under conditions which left acyl or carbalkoxy substituents unaffected. Pyrrole reactions involving carbanionic reagents are complicated by 1-proton abstraction. Therefore, when necessary, the nitrogen was protected by an N-benzyloxymethyl substituent which can be cleaved to the N-hydroxymethyl derivative by aluminum chloride or by hydrogenolysis. Subsequent treatment with benzyltrimethylammonium hydroxide gave back the pyrrole.

The spirobenzylisoquinoline system has been synthesized from substituted 2-phenyl-1,3-indandiones as starting materials. Ring B of the spiro system was constructed by a modified Pomeranz–Fritsch reaction. The reaction sequence has been applied to the synthesis of an analog of ochrobirine and then to (±)-ochrobirine itself.

Ausgehend vom Indandion (Ia) wird über das Bromderivat (Ib) mit Aminoacetaldehyddiäthylacetal das Aminoderivat (Ic) [72% Ausbeute, bezogen auf (Ia)] dargestellt.