Effect of Substituents in the Syntheses of Phenyl‐Substituted Dibenzonaphthyridines

Abstract

A facile and elegant syntheses of linear and angular phenyl‐substituted dibenzonaphthyridines from 2,4‐dichloroquinolines through anilinoquinolines have been developed. The substituents in the 4th position of the anilinoquinoline and the temperature were found to play a vital role in the regulation of the yield towards the synthesis of the final compounds. The methyl group in the 7th position of the naphthyridin‐11‐ones was found to hinder the N‐methylation reaction sterically, consequently increasing the reaction time than other derivatives.

Synthesis of novel benzo naphtho naphthyridines from 2,4‐dicloroquinolines

“…From the above point of observations, the final products in both cases ( 5a and 12a ) one proton gets deshielded in each case, which is shown in Figure 1. Finally, we have compared the most recently reported 24–30 catalysts and the solvent condition was shown in Table 3. The selective amination reaction involving various aromatic amines thereby deriving the respective anilino‐analogs with their reaction conditions according to their catalyst investigation based on solvent performances.…”

Benzoquinoline amines – Key intermediates for the synthesis of angular and linear dinaphthonaphthyridines

“…All the spectral data revealed the formation of the compound 13 . Here the chance of getting the linear naphthyridine 14 has not been observed and the only formed product was assigned as the thermodynamically more stable angular isomer namely, N -(naphth-1″-yl)-7-(4′-methylphenyl)-dinaphtho[1,2- b :1′,2′- h ][1,6]naphthyridin-6-amine 13 , on the basis of its higher melting point and literature data [33,34] ( Scheme 5 ).…”

Adipostatins E-J, new potent antimicrobials identified as inhibitors of coenzyme-A biosynthesis

“…A recurring bioactivity guided preparative C18 fractionation (Fig SI -7) and ensuing yielded two known adipostatins A-B (6)(7), which were also reported to be isolated from Streptomyces sp., 18 and six new congeners, adipostatins E-J (10)(11)(12)(13)(14)(15) with structures likely derived from a type I polyketide synthase pathway.…”

“…18 Furthermore, 6 and 7 in addition to two more congeners adipostatins C-D (8)(9) have been recently reported to possess anti-parasitic activity, 19 however 8 and 9 were not observed in our study. Adipostatin E (10) was purified as light yellow amorphous solid possessing the molecular formula of C 22 H 38 O 2 based on [M+H] + ion peak m/z 335.2899 . The 1 H and 13 C NMR data, recorded in CD 3 OD, indicated the polyketidic nature of 10 with the tell-tale presence of 1 H NMR peak at δ 1.31 suggesting an aliphatic chain consisting primarily of methylene groups.…”

“…8,9 Type II PPCSs, expressed as monofunctional enzymes, utilize either ATP or CTP and can be found mainly in eukaryotes. 10,11 Type III PPCSs, also expressed monofunctionally, have been shown to be CTP specific and are found in a smaller subset of bacteria. 11 Although the peculiar nucleotide selectivity could be an attractive target for the design of bacterial inhibitors validated by a series of intermediate-mimicking inhibitors, 11 no novel chemical structures have been identified.…”