Preparation, structure and addition reactions of 4- and 5-aminoimidazoles

Al-Shaar, Adnan H. M.; Gilmour, David W.; Lythgoe, David J.; McClenaghan, Ian; Ramsden, Christopher A.

doi:10.1039/p19920002779

Cited by 35 publications

(17 citation statements)

References 35 publications

(4 reference statements)

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“…Previously 2 we suggested two synthetic routes to N‐arylphosphinimidic isocyanates, viz., the reaction of arylazides with an appropriate phosphorus(III) isocyanate and the reaction of chlorophosphine N‐arylimides with alkali metal cyanates on heating. Here, we employ the second method starting from previously described 3 5‐amino‐1,2‐dimethylimidazole 1 as a precursor of phosphinimidic chloride 4 (Scheme ). It should be noted that dehydrohalogenation of phosphonium salt 3 requires the presence of potassium tert‐butoxide, a relatively strong base, whereas triethylamine frequently used in such reactions is not strong enough.…”

Section: Resultsmentioning

confidence: 99%

Intramolecular cyclization of N‐hetarylphosphinimidic isocyanates in the synthesis of 1,7‐dihydro‐4H‐imidazo[4,5‐d][1,3,2]diazaphosphinin‐4‐one (2‐phosphapurine)

Anatoliy¹,

Georgiy²,

Anastasia³

et al. 2010

Heteroatom Chemistry

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It has been found that N‐(4‐imidazolyl)phosphinimidic isocyanates obtained by the reaction of the corresponding chlorophosphine N‐hetarylimide with alkali metal cyanates can undergo intramolecular heterocyclization to yield previously unknown phosphapurine derivatives containing an endocyclic PN double bond. This radically novel approach to building the 2‐phosphapurine system shows promise for the synthesis of related phosphorus‐containing fused heterocycles. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:453–455, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20617

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Section: Resultsmentioning

confidence: 99%

Intramolecular cyclization of N‐hetarylphosphinimidic isocyanates in the synthesis of 1,7‐dihydro‐4H‐imidazo[4,5‐d][1,3,2]diazaphosphinin‐4‐one (2‐phosphapurine)

Anatoliy¹,

Georgiy²,

Anastasia³

et al. 2010

Heteroatom Chemistry

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“…The preparation of O-alkylimidates 193 from -aminonitriles 192 and subsequent co-cyclization of such imidates with primary amines to afford 4-substituted 5-aminoimidazoles 194 (Scheme 61) previously has been documented in the literature [110][111][112][113][114][115].…”

Section: Formation Of a Five-membered Ring With Two Heteroatomsmentioning

confidence: 99%

Utilities of Some Carbon Nucleophiles in Heterocyclic Synthesis

Madkour¹,

Elgazwy

2007

COC

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New developments in the utilities of some carbon nucleophiles in heterocyclic synthesis are reviewed. General synthetic routes based on the utilization of carbon nucleophiles of active methylene are discussed. The major methods and modifications are analyzed. Heterocycles are ubiquitous in all kind of compounds of interest, and among all the possible synthetic methods of achieving their introduction into a structure, probably the use of a carbon nucleophile analogues are the most direct one. The present review deals with the generation and synthetic of carbon nucleophile, which uses as scaffold for the heterocyclic synthesis, and can be considered as an update review. Therefore the only references published upon the second quarter of 2003 are included, and the same restrictions to the literature coverage apply.

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“…Use of ethoxymethylene malononitrile as electrophile gave exclusively the C-addition-elimination product 22 in accord with our previous work with 5-aminoimidazoles. 19,29,30 Compound 22 showed a primary amine signal ( 7.72 ppm) and a single imidazole proton ( 7.83 ppm).…”

Section: 28mentioning

confidence: 99%

Preparation of pyridine-stretched 2'-deoxyhypoxanthosine phosphoramidite

Clayton¹,

Davis

et al. 2017

Arkivoc

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Pyridine-stretched 2′-deoxyhypoxanthosine (strH) phosphoramidite was prepared in eight steps from Hoffer's sugar (2′-deoxy-3,5-di-O-(p-toluoyl)--D-erythro-pentofuranosyl chloride). Improved synthesis of the Hoffer sugar was achieved without need for distillation or chromatographic separation of intermediates, or use of gaseous HCl. Conditions were optimised to provide a key nitrile intermediate for the preparation of strH whereby the cesium salt of 4(5)-nitroimidazole was glycosylated using Hoffer's sugar. The nitrile intermediate was also used to prepare pyridine-stretched 2′-deoxyadenosine (strA) and pyridine-stretched 2′-deoxy-2,6-diaminonebulamine (strD). Preliminary studies indicate that strH forms a stronger, size-expanded base pair with adenine compared with the Watson-Crick thymine-adenine base pair.

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Preparation, structure and addition reactions of 4- and 5-aminoimidazoles

Cited by 35 publications

References 35 publications

Intramolecular cyclization of N‐hetarylphosphinimidic isocyanates in the synthesis of 1,7‐dihydro‐4H‐imidazo[4,5‐d][1,3,2]diazaphosphinin‐4‐one (2‐phosphapurine)

Intramolecular cyclization of N‐hetarylphosphinimidic isocyanates in the synthesis of 1,7‐dihydro‐4H‐imidazo[4,5‐d][1,3,2]diazaphosphinin‐4‐one (2‐phosphapurine)

Utilities of Some Carbon Nucleophiles in Heterocyclic Synthesis

Preparation of pyridine-stretched 2'-deoxyhypoxanthosine phosphoramidite

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