Imidazopyridine Research Articles

ChemInform Abstract: The Reaction of Imidazo(1,5‐a)pyridines with Methyl‐ and Phenyltriazolinediones and with Diethyl Azodicarboxylate.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Polyfunctional Pyridines from Nitroacetamidine and β‐Diketones. A Useful Synthesis of Substituted Imidazo(4,5‐b)pyridines and Related Compounds.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: A New and Efficient Synthesis of Imidazo(1,5‐a)pyridine Derivatives by a Tandem Aza‐Wittig / Electrocyclic Ring Closure of N‐Vinylic Phosphazenes

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: New Synthetic Route to Imidazo(4,5‐c)pyridines by the Thermal Electrocyclic Reaction of 1‐Azahexatriene Systems.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Synthesis of Imidazo(4,5‐c)pyridines with a Trifluoromethyl Group at C‐ 4 and/or C‐6.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: New Process for the Synthesis of Imidazo(4,5‐b)pyridine Derivatives as Potent Orally Active Thromboxane A2 Receptor Antagonists.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A QSAR study of the biological activities of some benzimidazoles and imidazopyridines against Bacillus subtilis

Summary A set of benzimidazole (1) and imidazopyridine (II) derivatives that have previously been tested for their antibacterial activities against Bacillus subtilis were analyzed using the quantitative structure-activity relationship (QSAR) method. The activity contributions for structural and substituent effects were determined from the correlation equations, which were derived using all possible combination and stepwise regression techniques. The best equation was chosen among the other equations by considering the various statistical criteria. The resulting QSAR revealed that the activity contributions of benzimidazoles and imidazopyridines against B subtilis depend almost entirely on their relative lipophilic character as defined by their octanol/water partition coefficients, log P . The ideal lipophilic character for the investigated imidazole nuclei has been found to be about 4.9.

QSAR Study on Antibacterial Effects of Benzimidazole and Imidazopyridine Derivatives

A set of benzimidazole (I) and imidazopyridine (II) derivatives previously tested for their antibacterial activities against Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli), and Bacillus subtilis (B. subtilis) were analyzed by quantitative structure-activity relationship (QSAR) and the activity contributions for structural and substituent effects were determined using multiple regression procedure. The resulting QSAR revealed that for the activity contribution against S. aureus and P. aeruginosa the substituents of p-position on the phenyl moiety play important role, and besides the p-substituents the substituents in other positions improve the activity. For the potency against E. coli, the character of six membered ring of the fused ring system becomes important besides the substituents effects at the p-position of the phenyl group. It was also found that both the benzimidazole ring system and p-substituted benzyl moiety have significant structural effects besides the lipophilicity of the substituents at R3 for the activity against B. subtilis.

ChemInform Abstract: Anti‐HIV Agents. Part 3. Synthesis and in vitro Anti‐HIV Activity of Novel 1H,3H‐Thiazolo(3,4‐a)imidazo(4,5‐b)pyridines.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Pyrrolo(1′,2′:1,2)imidazo(4,5‐b)pyridines, Pyrrolo(2′,1′:2,3)imidazo(4, 5‐c)pyridines and Pyrrolo(2,1‐f)purines as Potential Benzodiazepine Ligands.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Synthesis and Evaluation of Gastroprotective Activity of Omeprazole Related Benzimidazole, Imidazo(4,5‐b)pyridine and Quinoxaline 2‐ Substituted Derivatives.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Site Selective Alkoxymethylation of Imidazo(4,5‐b)pyridines: Structural Analysis by High Field NMR Methods.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Altered jejunal potassium (Rb+) transport in piglet rotavirus enteritis.

To determine the mechanisms of K+ loss in viral diarrhea, K+ fluxes (estimated by tracer Rb+ flows) across piglet jejunum in Ussing chambers were determined. Normal jejunum was characterized by an indomethacin-sensitive short-circuit current and a small K+ secretory flow. Rotavirus-infected gut secreted K+ at high rates, probably resulting from increased prostaglandin generation because secretion was abolished by indomethacin. Tissues pretreated with indomethacin responded to 8-bromoadenosine 3',5'-cyclic monophosphate acid and 16,16-dimethyl-prostaglandin E2 with K+ secretion. The secretory response in rotavirus-infected jejunum was no greater than that in normal tissue. Serosal addition of Ca2+ ionophore A23187 caused K+ secretion in normal but not rotavirus-infected jejunum. To inhibit the basolateral uptake of K+ and reduce the driving force for secretion, ouabain was added to the bath. Ouabain unmasked a K+ absorptive process in normal intestine, which was not seen in rotavirus-infected tissue. K+ absorption was inhibited by 3-(cyanomethyl)-2-methyl-8-(phenyl-methoxy)imidazo (1,2 alpha)pyridine (Sch-28080) and omeprazole. We speculate that the high fecal K+ losses observed in human rotavirus enteritis might be caused by an imbalance between K+ secretion and an impaired apical K+ absorptive mechanism in the crypt-type epithelium.

ChemInform Abstract: Synthesis of Functionalized N‐(2‐Pyridyl)‐α‐amino Acids and Esters by Ring Opening of Imidazo(1,2‐a)pyridine.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Imidazo(4,5‐b)pyridine Derivatives of Potential Tuberculostatic Activity. Part 1. Synthesis and Quantitative Structure‐Activity Relationships.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Synthesis of New Derivatives in a Series of Imidazo(1,2‐a)pyridines of Potential Pharmacological Activities by SRN1 Reaction.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A New Route to Imidazo(1,5-a)pyridines and -quinolines

A new synthetic approach for imidazo(1,5-a)pyridines and imidazo(1,5-a)quinolines from the corresponding alkyl(pyridyl-2′)- or (quinolyl-2′)glycinates is described.

ChemInform Abstract: Synthesis and Antitumor Evaluation in Mice of Certain 7‐Deazapurine (Pyrrolo(2,3‐d)pyrimidine) and 3‐Deazapurine (Imidazo(4,5‐c)pyridine) Nucleosides Structurally Related to Sulfenosine, Sulfinosine, and Sulfonosine.

7-Deaza (pyrrolo[2,3-d]pyrimidine) and 3-deaza (imidazo[4,5-c]pyridine) congeners of sulfenosine (5a and 9), sulfinosine (6a and 10), and sulfonosine (7a) have been prepared and evaluated for their antileukemic activity in mice. Amination of 2-amino-7-beta-D-ribofuranosylpyrrolo[2,3-d]pyrimidine-4(3H)-th ion e (4a) and its 2'-deoxy analogue (4c) with a chloramine solution gave the corresponding 4-sulfenamides (5a and 5c, respectively), which on selective oxidation with m-chloroperoxybenzoic acid (MCPBA) gave the respective diastereomeric 2-amino-7-beta-D-ribofuranosyl-pyrrolo[2,3-d]pyrimidine-4-sulfinamide (7-deazasulfinosine, 6a) and its 2'-deoxy derivative (6c). A similar amination of 7-(2-deoxy-beta-D-erythro-pentofuranosyl)pyrrolo[2,3-d]pyrimidine-4(3H)- thione (4b) gave the corresponding 4-sulfenamide derivative (5b). Oxidation of 5b with 1 molar equiv of MCPBA furnished (R,S)-7-(2-deoxy-beta-D-erythro-pentofuranosyl)pyrrolo[2,3-d]pyrimidine- 4- sulfinamide (6b), whereas use of excess of MCPBA afforded the corresponding sulfonamide derivative (7b). Treatment of 3-deaza-6-thioguanosine (8) with a chloramine solution gave 3-deazasulfenosine (6-amino-1-beta-D- ribofuranosylimidazo[4,5-c]pyridine-4-sulfenamide, 9). Controlled oxidation of 9 with MCPBA afforded 3-deazasulfinosine (10). As gauged by increases in the mean postinoculation life spans of L1210 inoculated mice, none of these nucleosides exhibited biologically significant activity (T/C greater than or equal to 125). Even so, antileukemic activity appeared to be influenced, albeit not uniformly, by structural modifications in the base and carbohydrate moieties of sulfenosine and sulfinosine. Thus, while several of the compounds were lacking in cytotoxic activity, eight others (4c, 5a, 5c, 6a, 6b, 7b, 9, and 10) were estimated to have reduced body burdens of viable L1210 cells by 16-77%.

ChemInform Abstract: A Novel Preparation of Thiazolo(5,4‐c)pyridines and the Synthesis of Some Imidazo(4,5‐c)pyridines and Oxazolo(4,5‐c)pyridines.

Diethoxymethyl acetate was used to cyclize o-disubstituted aminopyridines to oxazolo[4,5-c]pyridines and imidazo[4,5-c]pyridines. All the possible imidazole-methylated imidazo[4,5-c]pyridines were prepared. A novel synthesis of 2-substituted thiazolo[5,4-c]pyridines and 4-amino-3-pyridinethiol was discovered.

ChemInform Abstract: Imidazole Derivatives. Part 3. Regiospecific Synthesis, Structure, and Fluorescence Properties of Highly Substituted Imidazo(1,2‐a)pyridines and Pyrido(1,2‐a)benzimidazoles.

Abstract1‐(Arylacetyl)imidazoles such as (I) react with acetylenedicarboxylates such as (II) to give the imidazo(1,2‐a)pyridines (III); a strong effect on the yield is observed for electron‐donating and electron‐withdrawing substituents in the para‐position of the aryl ring (X‐ray analysis of (IIIa): space group P21/c, Z=4).