2-Aza-3-oxabicyclo[2.2.1]heptene hydrochloride: An exceptionally versatile synthon for carbocyclic sugars and nucleosides
摘要:
The transformation of cyclopentadiene to 5'-desmethylene 1'-aza carbocyclic sugars has been achieved in four steps: 1. Cycloaddition of chloronitrosocyclohexane to 2-aza-3-oxabicyclo[2.2.1]heptene hydrochloride in EtOH-Et(2)O, 2. Nitrogen functionalization, 3. cis hydroxylation and 4. N-O bond cleavage. The protocols provided enable practical access to a range of 5'-desmethylene carbocyclic sugar analogs whose utility has been illustrated with synthesis of a novel 5'-desmethylene analog of aristeromycin. (C) 1997 Elsevier Science Ltd.
2-Aza-3-oxabicyclo[2.2.1]heptene hydrochloride: An exceptionally versatile synthon for carbocyclic sugars and nucleosides
摘要:
The transformation of cyclopentadiene to 5'-desmethylene 1'-aza carbocyclic sugars has been achieved in four steps: 1. Cycloaddition of chloronitrosocyclohexane to 2-aza-3-oxabicyclo[2.2.1]heptene hydrochloride in EtOH-Et(2)O, 2. Nitrogen functionalization, 3. cis hydroxylation and 4. N-O bond cleavage. The protocols provided enable practical access to a range of 5'-desmethylene carbocyclic sugar analogs whose utility has been illustrated with synthesis of a novel 5'-desmethylene analog of aristeromycin. (C) 1997 Elsevier Science Ltd.
Stereo- and Regioselectivity of Pd<sup>0</sup>/InI-Mediated Allylic Additions to Aldehydes and Ketones. <i>In Situ</i> Generation of Allylindium(III) Intermediates from <i>N</i>-Acylnitroso Diels−Alder Cycloadducts and 1-Amino-4-acetoxycyclopentenes
作者:Wenlin Lee、Kyung-Hee Kim、Matthew D. Surman、Marvin J. Miller
DOI:10.1021/jo026488z
日期:2003.1.1
and regiochemistry of their additions to aldehydes and ketones were investigated. Solvent, catalyst, and ionic effects were examined for the reaction of N-acetyl cycloadduct (11) and benzyloxyacetaldehyde (10). The solvent mixture of THF/H(2)O with Pd(OAc)(2).PPh(3) catalysis was found to be optimal. The addition of N-acetyl cycloadduct to aliphaticaldehydes afforded products in good yields and high
Synthesis and evaluation of 5-lipoxygenase translocation inhibitors from acylnitroso hetero-Diels–Alder cycloadducts
作者:Joshua K. Bolger、Wen Tian、William R. Wolter、Wonhwa Cho、Mark A. Suckow、Marvin J. Miller
DOI:10.1039/c0ob00714e
日期:——
Acylnitroso cycloadducts have proven to be valuable intermediates in the syntheses of a plethora of biologically active molecules. Recently, organometallic reagents were shown to open bicyclic acylnitroso cycloadducts and, more interestingly, the prospect of highly regioselective openings was raised. This transformation was employed in the synthesis of a compound with excellent inhibitory activity against 5-lipoxygenase ((±)-4a, IC50 51 nM), an important mediator of inflammation intimately involved in a number of disease states including asthma and cancer. Optimization of the copper-mediated organometallic ring opening reaction was accomplished allowing the further exploration of the biological activity. Synthesis of a number of derivatives with varying affinity for metal binding as well as pendant groups in a range of sizes was accomplished. Analogues were tested in a whole cell assay which revealed a subset of the compounds to be inhibitors of enzyme translocation, a mode of action not previously known and, potentially, extremely important for better understanding of the enzyme and inhibitor development. Additionally, the lead compound was tested in vivo in an established colon cancer model and showed very encouraging anti-tumorogenic properties.
Diaryl ether containing N-hydroxycarbamates from nitroso cycloadducts
作者:Joshua Bolger、Marvin Miller
DOI:10.1016/j.tetlet.2011.02.016
日期:2011.4
Regioselective ring opening of N-hydroxycarbamate-derived nitroso cycloadducts by a copper-catalyzed allylic alkylation reaction was achieved and applied to the synthesis of a set of substituted diaryl ether containing compounds. Use of protected 3-hydroxybenzyl bromide allowed access to a late stage phenol intermediate after protection of the N-hydroxy moiety that was generated from the ring opening reaction. The diaryl ethers were then formed by copper-mediated coupling with arylboronic acids. After selective deprotection, alumina-promoted transcarbamoylation provided the target compounds. Previous results indicate that the compounds may possess significant inhibitory potency against the proinflammatory enzyme 5-lipoxygenase. (C) 2011 Elsevier Ltd. All rights reserved.
KECK G. E.; FLEMING S.; NICKELL D.; WEIDER P., SYNTH. COMMUN., 1979, 9, NO 4, 281-286
作者:KECK G. E.、 FLEMING S.、 NICKELL D.、 WEIDER P.
DOI:——
日期:——
2-Aza-3-oxabicyclo[2.2.1]heptene hydrochloride: An exceptionally versatile synthon for carbocyclic sugars and nucleosides
作者:Subramania Ranganathan、K.Shaji George
DOI:10.1016/s0040-4020(97)00057-4
日期:1997.3
The transformation of cyclopentadiene to 5'-desmethylene 1'-aza carbocyclic sugars has been achieved in four steps: 1. Cycloaddition of chloronitrosocyclohexane to 2-aza-3-oxabicyclo[2.2.1]heptene hydrochloride in EtOH-Et(2)O, 2. Nitrogen functionalization, 3. cis hydroxylation and 4. N-O bond cleavage. The protocols provided enable practical access to a range of 5'-desmethylene carbocyclic sugar analogs whose utility has been illustrated with synthesis of a novel 5'-desmethylene analog of aristeromycin. (C) 1997 Elsevier Science Ltd.