- Preparation method 4 - hydroxyl -2 - butynoic acid
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The 4 -hydroxyl -2 - butynoic acid preparation method comprises 1, 4 - butynediol as a raw material in an organic solvent and N-O free radical catalyst. The ferrous salt or ferrous salt hydrate or iron salt or iron salt hydrate is oxidized by air or oxygen to obtain 4 - hydroxyl -2 - butyneic acid under the synergistic catalysis of air or oxygen. To the method, the alkyl lithium method commonly adopted in the present production is avoided, the process safety is greatly improved, the production cost is reduced, and the selectivity is close 100% under the optimized process conditions.
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Paragraph 0027-0035
(2021/11/19)
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- Ruthenium-catalyzed asymmetric [2 + 2] cycloadditions between chiral acyl camphorsultam-substituted alkynes and bicyclic alkenes
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Ruthenium-catalyzed asymmetric [2 + 2] cycloadditions between chiral acyl camphorsultam-functionalized alkynes and bicyclic alkenes were examined, providing adducts with complete exo stereoselectivity in good overall yield and enantioselectivity (up to 99% and 166:1, respectively), as well as appreciable diastereoselectivity (up to 163:1). The diastereoselectivity showed dependence on the solvent and temperature, as well as on the substitution pattern of the reacting alkyne and bicyclic alkene components. In general, higher diastereoselectivities were observed for reactions conducted in ethereal solvents and at lower temperatures between N-propynoyl camphorsultams and bicyclic alkenes.
- Goodreid, Jordan,Villeneuve, Karine,Carlson, Emily,Tam, William
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p. 10002 - 10012
(2015/02/19)
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- Microbial Transformation of 2-Butyn-1,4-diol into 4-Hydroxy-2-butynoic Acid by Specific Oxidation of the Hydroxymethyl Group
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2-Butyn-1,4-diol was oxidized quantitatively by the liophilized cell of Rhinocladiella atrovirens KY801 to afford the monocarboxylated product, 4-hydroxy-2-butynoic acid.Neither aldehydes nor degrading compounds were detected in the reaction mixture.
- Matsumura, Shuichi,Yoda, Nobuo,Endo, Masato,Yoshikawa, Sadao
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p. 647 - 648
(2007/10/02)
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- Prodrugs Based on Masked Lactones. Cyclization of γ-Hydroxy Amides
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A versatile approach to prodrug design based on the lactonization of γ-hydroxy carbonyl compounds is investigated.A range of γ-hydroxy amides have been synthesized as models for amide-linked prodrugs.The rates of lactonization of these compounds have been measured, and the effects of pH, leaving group pKa, buffer species, and ionic strength are investigated.The kinetic data are consistent with changes in the rate-determining step with the nature of the buffer and with pH over the range 6-10.Some compounds show only small changes in rate over the pH range 7-9.The best model prodrugs studied have rates of amine expulsion that would probably be adequate for therapeutic use, but precise rates of drug liberation in vivo cannot be predicted from these data due to the problems of estimating the magnitude of biological buffer catalysis and effects due to tissue binding.However, drug liberation half-lives in vivo in the region of 1 h for aromatic amides, less for aliphatic amides, may be achieved by using prodrugs that yield 4,4-dialkyl(or spiroalkyl)-(Z)-but-2-enoic acid lactones during drug release.
- Johnson, C. David,Lane, Simon,Edwards, Philip N.,Taylor, Peter J.
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p. 5130 - 5139
(2007/10/02)
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