The Synthesis of 6H-Pyrido[4,3-b]carbazoles

Emerging Targets in the Bioactivity of Ellipticines and Derivatives

“…While the alternating sequence offers two distinct binding sites, only the 5 0 TA site was considered as other intercalators had exhibited an apparent preference for 5 0 pyrimidinepurine sites. Using a model developed from a crystal structure of ellipticine complexed with 5-iodocytidylyl- (3,5)guanosine monophosphate and following initial molecular mechanical studies to identify the most likely binding orientations, they carried out MD simulations starting from four different orientations of the drug as follows: the long axis of the drug parallel to the long axis of the base pairs with N6 pointing into the minor groove and into the major groove and the long axis of the drug perpendicular to the long axis of the base pairs with N2 pointing into the major and into the minor groove. To enable determination of the effects of intercalation on the structure of the DNA sequence, an MD simulation of the free oligomer was first carried out, with the characteristics of the end structure (parameters such as rise and twist angles) being broadly in agreement with experimental data, thus providing some validation for the system.…”

“…It has been the focus of extensive chemical and pharmacological research since the discovery of its antitumor effects [2]. Multiple synthetic routes to ellipticine have been developed; these have been reviewed comprehensively by Sainsbury [3], Gribble and Saulier [4], and Miller and McCarthy [5]. Biologically, ellipticine presents a challenging and interesting focus of research.…”

Dihydropyridines in synthesis and biosynthesis. V. Synthesis of pyridocarbazole alkaloids: olivacine and (±)-guatambuine

“…The total synthesis of representa-afforded the tricarbonylchromium(0) complex 8 as tives of this family of alkaloids has been the subject red crystals in 56% overall yield. High resolution of numerous studies (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21). Several of the syn-'Hmr revealed two sets of resonances, indicating thetic approaches reported employed cyclization the product as a mixture of two diastereoisomers in of pyridyl-substituted indoles to generate the linear the ratio of 2: 1 (see Experimental).…”

A novel synthetic approach for the synthesis of pyridocarbazole alkaloids

“…The 6H-pyrido [4,3-b]carbazole alkaloids are tetracyclic. The synthetic strategies for the preparation of the tetracyclic 6H-pyrido [4,3-b]carbazole alkaloids are classified in four main groups, such as B type, C type, B+C type and D type, based upon the last ring to be constructed [13,14].The B type synthesis includes Goldberg's coupling of substituted nitro anilines with a bromo isoquinoline derivative. The B ring is constructed with the subsequent reactions [15].…”