Synthesis Of Pyrrolo Research Articles

Synthesis of Pyrrolo[1,2-b]isoquinolines through Mesityllithium-Mediated Intramolecular Carbolithiation

Mesityllithium has proven to be an effective iodine-lithium exchange reagent. Thus, carbolithiation reactions on 2-alkenyl-substituted N-(o-iodobenzyl)pyrroles have been accomplished avoiding side reactions to afford pyrroloisoquinolines in high yields (80-92%), improving the results obtained with t-BuLi. The carbolithiation reaction requires the use of electron-deficient alkenes. Mesityllithium has also been studied as an alternative to t-BuLi in Parham cyclization with other internal electrophiles (aldehyde, ketone, ester, amide), proving to be more selective and efficient than t-BuLi.

ChemInform Abstract: A New Synthesis of Pyrrolo[3,2‐b]quinolines (V) by a Tandem Electrocyclization—Oxidation Process.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 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.

3-Aminopyrroles and their application in the synthesis of pyrrolo[3,2-d]pyrimidine (9-deazapurine) derivatives

Aminopyrrole derivatives have been synthesized from 3-anilino-2-cyanoacrylonitrile using Thorpe-Ziegler cyclization. These substituted pyrroles are readily converted into 5H-pyrrolo(3,2- d)pyrimidine (9-deazapurines).

ChemInform Abstract: Indium Chloride Catalyzed Intramolecular Cyclization of N‐Aryl Imines: Synthesis of Pyrrolo[2,3‐d]pyrimidine Annulated Tetrahydroquinoline Derivatives.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 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 synthesis of pyrrolo[3,2- b]quinolines by a tandem electrocyclization–oxidation process

A new synthesis of pyrrolo[3,2- b]quinolines is described. Condensation of anilines with dimethyl 4-oxopyrrolidine-1,3-dicarboxylate yields enaminoesters, which upon reaction with Bredereck's reagent produce the title compounds. A possible reaction mechanism is briefly discussed.

First example of the synthesis of pyrrolo[1,2-d][1,4]diazocine by the reaction of tetrahydropyrrolo[1,2-a]pyrazines with activated alkynes

First example of the synthesis of pyrrolo[1,2-d][1,4]diazocine by the reaction of tetrahydropyrrolo[1,2-a]pyrazines with activated alkynes

Indium chloride catalyzed intramolecular cyclization of N-aryl imines: synthesis of pyrrolo[2,3- d]pyrimidine annulated tetrahydroquinoline derivatives

The intramolecular aza Diels–Alder cyclization reaction of aldimines derived from aromatic amines and N-prenyl/cinnamyl derivatives of pyrrolo[2,3- d]pyrimidine were efficiently catalyzed by InCl 3 to afford the corresponding tetrahydroquinoline derivatives in good yields.

A new method for the synthesis of pyrrolo[1,2-a]quinolines based on boron trifluoride-mediated cyclization of 1-(2-oxiranylphenyl)pyrroles

A new method for the synthesis of pyrrolo[1,2-a]quinolines based on boron trifluoride-mediated cyclization of 1-(2-oxiranylphenyl)pyrroles

Synthesis of Pyrrolo[2,1‐a]isoquinolines by a Tandem 1,5‐Electrocyclization—Oxidation Process.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Synthesis of Pyrrolo[1,2‐b]pyridazine Derivatives Engrafted on N‐Acylphenothiazine.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Enamines of the 1,2,3,4-tetrahydroiso-quinoline series in the Chichibabin synthesis of pyrrolo[2,1-a]isoquinolines and in reaction with oxalyl chloride

It has been shown that the Chichibabin reaction of enamines of the 1,2,3,4-tetrahydroisoquinoline series and 1,2,3,4-tetrahydrobenzo[f]isoquinoline series with p-bromophenacyl bromide leads to pyrrolo[2,1-a]isoquinoline derivatives. The same heterocyclic system is obtained on interaction of 1-alkyl-3,4-dihydroisoquinolines or their benzo[f]-analogs with oxalyl chloride. The obtained dioxopyrrolines form derivatives of benzo[g]quinoxalino[2,3-b]indolizine on condensation with o-phenylenediamine.

Novel Oxidation of Substituted Pyrrolidines by N-Bromosuccinimide - Rapid Synthesis of Pyrrolo[2,1-a]isoquinolines

A new method for converting 1,2,3,5,6,10b-hexahydro-pyrrolo[2,1-a]isoquinolines into 5,6-dihydropyrrolo[2,1-a]isoquinolines by the use of N-bromosuccinimide as an oxidant is presented.

Synthesis of pyrrolo[2,3-d]pyridazinones as potent, subtype selective PDE4 inhibitors

A series of pyrrolo[2,3-d]pyridazinones was synthesized and tested for their inhibitory activity on PDE4 subtypes A, B and D and selectivity toward Rolipram high affinity binding site (HARBS). New agents with interesting profile were reported; in particular compound 9e showed a good PDE4 subtype selectivity, being 8 times more potent (IC50 = 0.32 μM) for PDE4B (anti-inflammatory) than for PDE4D (IC50 = 2.5 μM), generally considered the subtype responsible for emesis. Moreover the ratio HARBS/PDE4B was particularly favourable for 9e (147), suggesting that the best arranged groups around the pyrrolopyridazinone core are an isopropyl at position-1, an ethoxycarbonyl at position-2, together with an ethyl group at position-6.For compounds 8 and 15a the ability to inhibit TNFα production in PBMC was evaluated and the results are consistent with their PDE4 inhibitory activity.

A new approach to the synthesis of pyrrolo[1,2-a]indole derivatives

Reactions of 2-(3,3-diamino-2-cyanoprop-2-enylidene)indolin-3-ones with amide acetals afforded derivatives of 3-aminomethyleneamino-2-cyano-9-oxo-9H-pyrrolo[1,2-a]indole and 3-amino-2-cyano-9-oxo-9H-pyrrolo[1,2-a]indole. The rate and pathway of the reaction depend on the reagents and solvents. The formation schemes for the compounds obtained were proposed. Their structures were proven by IR and 1H NMR spectroscopy and mass spectrometry and confirmed by independent syntheses.

A Synthesis of Pyrrolo[2,1‐a]isoquinolines Through the Reaction of Activated Acetylenes and Isoquinoline in the Presence of Ethyl Bromopyruvate.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

A Concise Synthesis of Pyrrolo‐ and Pyrrolidino[1,2‐a]quinolin‐1‐ones via Diels—Alder Reactions of N‐Acyliminium Cations with Olefins.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

TiCl4/t-BuNH2-Promoted Hydroamination/Annulation of δ-Keto-acetylenes: Synthesis of Novel Pyrrolo[1,2-a]indol-2-carbaldehydes

[reaction: see text] An original TiCl(4)/t-BuNH(2)-mediated hydroamination/annulation domino reaction of delta-keto-acetylenes is described. The synthesis of pyrrolo[1,2-a]indole-2-carbaldehydes, starting from 2-carbonyl-1-propargyl-1H-indoles runs under mild reaction conditions. A conceivable mechanism is also discussed. TiCl(4) has proved to be an effective multiactivity reagent: catalyst/Lewis acid/water scavenger. Some unpublished 2-carbonyl-1-propargyl-1H-indoles are prepared by means of Suzuki- and Negishi-type reactions.

Synthesis of pyrrolo[2,3- d]pyrimidine nucleoside derivatives as potential anti-HCV agents

Several Toyocamycin ( 4) analogues were examined for their ability to inhibit HCV RNA in a replicon assay. Among the compounds examined 4-methylthio ( 18) and 5-carboxamide oxime derivatives ( 23 and 27) of Toyocamycin were found to have good activity and selectivity.

Novel Synthesis of Pyrrolo[2,3‐d]pyrimidines Bearing Sulfonamide Moieties as Potential Antitumor and Radioprotective Agents.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

A synthesis of pyrrolo[2,1- a]isoquinolines through the reaction of activated acetylenes and isoquinoline in the presence of ethyl bromopyruvate

Isoquinoline reacts with ethyl bromopyruvate in the presence of dialkyl acetylenedicarboxylates or diaryloylacetylenes to produce dialkyl 1-(2-ethoxy-2-oxoacetyl)pyrrolo[2,1- a]isoquinoline-2,3-dicarboxylates or ethyl 2-[2,3-diaryloylpyrrolo[2,1- a]isoquinoline-1-yl]-2-oxoacetates in good yields.