Pyrrolo quinoline, synthesis from

Other indoles that have been prepared using the Sonogashira coupling and cyclization sequence include 5,7-difluoroindole and 5,6,7-trifluoroindole [219], 4-, 5-, and 7-methoxyindoles and 5-, 6-, and 7-(triisopropylsilyl)oxyindoles [220], the 5,6-dichloroindole SB 242784, a compound in development for the treatment of osteoporosis [221], 5-azaindoles [222], 7-azaindoles [160], 2,2-biindolyls [223,176], 2-octylindole for use in a synthesis of carazostatin [224], chiral indole precursors for syntheses of carbazoquinocins A and D [225], a series of 5,7-disubstituted indoles [226], a pyrrolo[2,3-eJindole [226], an indolo[7,6-g]indole [227], pyrrolo[3,2,l-y]quinolines from 4-arylamino-8-iodoquinolines [228], optically active indol-2-ylarylcarbinols [229], 2-alkynylindoles [176], 7-substituted indoles via the lithiation of the intermediate 2-alkynylaniline derivative [230], and a variety of 2,5,6-trisubstituted indoles [231], This latter study employs tetrabutylammonium fluoride, instead of Cul or alkoxide, to effect the final cyclization of 215 to indoles 216 as summarized here. 

B. Das et al. have also elaborated the microwave-assisted synthesis of Mappicine ketone, a potent antiviral lead compound derived from the natural product Camptothecin. The naturally occurring pyrrolo [ 3,4-6 ] quinoline... 

The Com synthesis was applied for the synthesis of pyrrolo[3,2- if]- and pyrrolo[2,3-0]quinolines (equation 120). Even during the synthesis of an enaminone from a... 

The versatility of this methodology is illustrated by Husson s regiocontrolled synthesis of pyrrolo[3,4-b]quinolin-9-ones (path A) and pyrrolo[2,3-c]quinolin-4-ones (path B) from l,2,4,5-tetrahydro-y9-carbolines 13a and 13b (Scheme 32) [65]. 

Similar methodology was employed for the synthesis of methyl-1, 3-dihydro-2H-pyrrolo[3,4- ]quinoline-2-carboxylate 162 in 65% yield and methyl-l,2-dihydro-3H-pyrrolo[3,4-h]quinoline-3-carboxylate 163 in 25% yield from commercial starting materials 160 and 161 (Scheme 31) (07S3319). 

Roberts D, Joule JA, Bros MA, Alvarez M (1997) Synthesis of pyrrolo[4,3,2-de]quinolines from 6,7-dimethoxy-4-methylquinoline. Formal total syntheses of damirones A and B, batzelline C, isobatzelline C, discorhabdin C, and makaluvamines A-D. J Org Chem 62 568-577... 

Ager IR, Barnes AC, Danswan GW, Hairsine PW, Kay DP, Kennewell PD, Matharu SS, Miller P, Robson P, Rowlands DA, Tully WR, Westwood R (1988) Synthesis and oral antiallergic activity of carboxylic acids derived from imidazo[2,l-c][l,4]benzoxazines, imidazo[l,2-tj] quinolines, imidazo[l,2-a]quinoxalines, imidazo[l,2-a]quinoxalinones, pyirolo[l,2-tj]quinox-alinones, pyrrolo[2,3-a]quinoxalinones, and imidazo[2,l-f>]benzothiazoles. J Med Chem 31 (6) 1098-1115. doi 10.1021/jm00401a009... 

Further studies with P. citrinum VKM FW-800 obtained from the permafrost region of Northern Russia, led to the isolation of the alkaloids (+)-quinocitrinine A and (—)-quinocitrinine B, which are diastereomers at the C-1 and C-9 stereocenters (186). These alkaloids were the first pyrrolo[3,4-lr]quinoline-type representatives isolated from microbial sources. Their structures are unique in that a quinolone skeleton is conjugated with a y-lactam ring. A biomimetic total S3mthesis of quinolactacin B was reported by Tatsuta s group (215). A new enantioselective synthesis of quinolactacins A2 and B, via the skeletal rearrangement of a p-carboline to the pyrrolo[3,4- ]quinolin-4(lf-D-one system by an... 

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