Isoquinoline, pyrrolo

Oxidations of several l-(3,4-dimethoxyphenyl)-2-(heteroaryl)ethanes with BTIB/Et20 BF3 have also been investigated (01SL1161). The 2-thienyl and 7V-pyrrolyl analogs 114 and 115 gave the naphthothiophene and pyrrolo-isoquinoline derivatives 116 (52%) and 117 (48%), respectively. However, the 2-furyl, 7V-methyl-2-pyrrolyl, and 6-methoxy-2-pyridyl congeners failed to give phenanthroid heterocycles under these conditions. 

The pyrrolo-isoquinoline (24) has been prepared as part of efforts directed towards the total synthesis of lycorine (Scheme 2).9 Treatment of the chloro-... 

To build the central ABC core present in 1, two main synthetic strategies have been used Diels-Alder reactions and asymmetric synthesis. This tricyclic subunit was chosen as the first synthetic target because it contains all five stereogenic carbons. A central pyrrolo-isoquinoline skeleton (ABC) was initially synthesized by the high-pressure Diels-Alder reaction of 3-alkyl-5,6-dihydro-2-pyridones with Danishefsky s diene, followed by deprotection and spontaneous pyrrolidine ring closure (see Scheme 16) [77]. 

Reaction of diphenylcyclopropenone with substituted 3,4-dihydroisoquinol-ines gives the corresponding pyrrolo-isoquinoline adduct (Scheme 93). ... 

Benzo[g]cycl[3.2.2]azines or pyrrolizino[3,4,5- 3]isoquinolines, for example, 366, are similarly obtained by cycloaddition of DMAD to pyrrolo[2,l- ]isoquinolines <1985CPB3038>, and l-aza-benzo[ ]cycl[3.2.2]azines are prepared by cycloaddition of DMAD to imidazo[2,l- ]iso-quinolines <1985H(23)2531> (Scheme 102). In all of the above cases, as with the simpler cyclazines, the ester functions are removable by hydrolysis in aqueous alkali followed by... 

Cronan T, Conrad 1, Bryson R (1985) Effects of chronically administered nicotine and saline on motor activity in rats. Pharmacol Biochem Behav 22 897-899 Damaj MI, Glassco W, Marks Ml, Slobe B, James JR, May EL, Rosecrans JA, Collins AC, Martin BR (1997) Pharmacological investigation of (-F)- and (—)-c. s-2,3,3a,4,5,9b-hexahydro-l-methyl-l/7-pyrrolo-[3,2-/ ]isoquinoline, a bridged-nicotine analog, J Pharmacol Exp Ther 282 1425-1434... 

Several tetra- and pentacyclic systems were prepared from Pro, which was first -substituted with naphthalene or phenanthrene rings whereupon the cyclization took place. Such reactions were used for synthetic ap-proaehes toward alkaloids vinceten from Cynachum vincetoxicum (the tetrahydrobenzo /]pyrrolo[l,2-Z ]isoquinoline system 146) (79LA1212 84AJC819) or tylophorine (65T2573). 

The fully unsaturated 1,3-benzodiazepine (135) is formed in a formally similar process by a photoreaction of the 1-substituted isoquinoline iV-imide (132) (80CPB2602). The same principle has been applied to the preparation of thieno-, furo- and pyrrolo-fused 1,3-diazepines (80CC454, 81 PB1539>. 

Scheme 29. Pyrrolo[2,3-i ]isoquinoline substructure synthesis via a 6-exo-trig radical cyclization...

In a recent example, Mironov used the rational replacement of starting materials for oligomerization reactions to discover new MCRs in a systematic way [31]. A reaction library of six alkenes/alkynes, two isonitriles, two nitriles and isoquinoline was set up, giving (n1 — n)/2 different reactions products. A minimum peak height of 30% of the total reaction product was used as a criterion for identifying an efficient MCR. In this way, a novel MCR that yields pyrrolo[2,l-a]isoquinolin-1-ones from electron-deficient olefins, isonitriles and isoquinoline was found (Scheme 10.6). 

Study of this receptor model led to the design of a series of 4a,8a-trans-pyrrolo [2,3-g] isoquinoline derivatives (e.g., Ro 22-1319, la)... 

Table III. Effect of ring size In cycloalka(4,5)pyrrolo(2,3-g) isoquinolines on activity.

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