SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
An effective methodology is reported for stereospecific epoxidation and aziridination via carbonyl ylide intermediates using rhodium(II) acetate catalyzed reactions of phenyl- and styryldiazoacetates with aldehydes, ketones, or imines.
[reaction: see text] Chiral aziridine derivative 1 was prepared from D-tartaric acid. This compound could be utilized as a common intermediate for the synthesis of hydroxyethylamine class HIV protease inhibitors such as saquinavir, amprenavir, or nelfinavir.
[reaction: see text] Sulfur ylide methodology has been used to construct the Taxol side chain with a high degree of enantioselectivity via a trans-aziridine followed by stereospecific rearrangement of the trans-benzoylaziridine into a trans-oxazoline.
A concise total synthesis of (+)-pseudodistomin D was developed. The absolute stereochemistry was established through a dynamic kinetic asymmetric cycloaddition of an isocyanate to a vinyl aziridine. The piperidine core was constructed through a silver(I)-catalyzed hydroamination of an alkyne and subsequent diastereo- and regioselective reduction. [reaction: see text]
[reaction: see text] A new route to substituted cyclic allylic amines via the reductive alkylation of beta-alkoxy aziridines using excess alkyllithium reagents is described.
[reaction: see text] An efficient, stereocontrolled assembly of the indolizidine alkaloid, (-)-indolizidine 223AB, exploiting a three-component linchpin coupling employing an N-Ts aziridine as the second electrophile, followed by a one-pot sequential construction of the indolizidine ring system, has been achieved. The longest linear sequence was 10 steps, proceeding in 10% overall yield.
[reaction: see text] The ustiloxins are a family of heterodetic cyclopeptides that have been isolated from the water extracts of false smut balls on the panicles of rice plants caused by the fungus Ustilaginoidea virens. A concise total synthesis of ustiloxin D has been achieved via an unprecedented ethynyl aziridine ring-opening of phenol derivatives. The longest linear sequence of the synthesis is 15 steps from commercially available compounds.
[reaction: see text] The chemoselective ring opening of N-tosyl aziridines with aldehydes catalyzed by an N-heterocyclic carbene was investigated under aerobic conditions. Unexpected carboxylates of 1,2-amino alcohols from the corresponding aldehydes, rather than the acyl anion ring-opened beta-amino ketones, were exclusively obtained. A plausible mechanism for this unprecedented carbene-mediated reaction was also proposed.
A new protocol for generating aza-ortho-xylylenes via acid-catalyzed or fluoride-promoted ring opening of 2-(2-acylaminophenyl)aziridines is described. This methodology has been exploited in the rapid construction of a hexacyclic substructure of communesin B.
An unprecedented stereo- and regioselective trisubstituted aziridine ring-opening by phenol derivatives was discovered. The reaction features very mild reaction conditions and broad functional group compatibility, which provides a good method for the stereoselective formation of tertiary alkyl-aryl ethers in highly functionalized systems. [reaction: see text]
A novel method is presented using N-N ylides (prepared by in situ amination of a tertiary amine) for the aziridination of a range of enone systems. The amine may be used sub-stoichiometrically, and promising levels of enantioselectivity are observed with quinine as promoter. [reaction: see text].
[reaction: see text] The N-chloramine salt of tert-butylsulfonamide has been shown to be an efficient nitrogen source and the terminal oxidant for catalytic aminohydroxylation and aziridination of olefins, resembling closely Chloramine-T by its behavior in these catalytic reactions. The sulfonyl-nitrogen bond in the product or its derivatives is easily cleaved under mild acidic conditions, allowing for facile liberation of the amino group.
[formula: see text] A catalytic method for the enantioselective ring opening of meso aziridines by TMSN3 is described. Tridentate Schiff base chromium complexes derived from 1-amino-2-indanol were identified as the optimal catalysts.
The first enantioselective reduction of aromatic 2H-azirines yields aziridines in up to 70% ee, using the aminoalcohol-[RuCl2(p-cymene)]2 catalyzed asymmetric transfer hydrogenation reaction.
Chiral aziridine sulfides and disulfides were synthesized from readily available and inexpensive R-cysteine by a Mitsunobu reaction; their application in the addition of diethylzinc to aldehydes provides secondary alcohols with up to 99% ee and S-configuration.
cis-Vinylic aziridines were prepared highly stereoselectively via a NaI-catalyzed regioselective ring-opening [1 + 2] cycloaddition reaction of cyclopropenes with imines.
A conceptually new, simple and practical method for the syn-nucleophilic displacement of aryl and vinyl epoxides and aryl aziridines with (substituted) phenols, using aryl borates as activating nucleophiles under neutral conditions, is reported.
Lewis acid-catalyzed ring expansion reaction of chiral aziridine-2-carboxylate proceeds regio- and stereospecifically to yield enantiomerically pure 4-functionalized imidazolidin-2-ones in high yields.