排序方式: 共有14条查询结果,搜索用时 93 毫秒
11.
Brands KM Jobson RB Conrad KM Williams JM Pipik B Cameron M Davies AJ Houghton PG Ashwood MS Cottrell IF Reamer RA Kennedy DJ Dolling UH Reider PJ 《The Journal of organic chemistry》2002,67(14):4771-4776
An efficient synthesis of the 2-aminocarbonylpyrrolidin-4-ylthio containing side chain of ertapenem (MK-0826) is described. Starting material N-(O,O-diisopropyl phosphoryl)-trans-4-hydroxy-L-proline is converted in a one-pot process to (2S)-cis-3-[[(4-mercapto-2-pyrrolidinyl)carbonyl]amino]benzoic acid monohydrochloride in 70-75% overall yield via a series of six reactions. The development of each of these reactions and the isolation of the product is discussed in detail. 相似文献
12.
Cameron J Cowden Deborah C Hammond Brian C Bishop Karel M.J Brands Antony J Davies Ulf-H Dolling Sarah E Brewer 《Tetrahedron letters》2004,45(32):6125-6128
An efficient method to prepare 3-substituted propionaldehyde derivatives using a Suzuki-Miyaura coupling is reported. The reaction has been demonstrated on a range of substrates including several where the Heck reaction with allyl alcohol failed to give the desired aldehyde product. 相似文献
13.
Williams JM Brands KM Skerlj RT Jobson RB Marchesini G Conrad KM Pipik B Savary KA Tsay FR Houghton PG Sidler DR Dolling UH DiMichele LM Novak TJ 《The Journal of organic chemistry》2005,70(19):7479-7487
[reaction: see text] A practical synthesis for the large-scale production of the new carbapenem antibiotic, [4R,5S,6S]-3-[[(3S,5S)-5-[[(3-Carboxyphenyl)amino]carbonyl]-3-pyrrolidinyl]thio]-6-[(1R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid monosodium salt (ertapenem sodium, 1), has been developed. The synthesis features the novel use of 1,1,3,3-tetramethylguanidine as base for the low-temperature reaction of a thiol, derived from trans-4-hydroxy-L-proline, with the carbapenem nucleus activated as the enol phosphate. Hydrogenolysis of a p-nitrobenzyl ester is effected using a palladium on carbon catalyst to give an overall yield for the two steps of 90%. The use of bicarbonate in the hydrogenolysis was key in providing protection of the pyrrolidine amine as the sodium carbamate improving both the performance of the reaction and the stability of the product. This discovery made processing at manufacturing scale possible. Experimental evidence for the formation of the sodium carbamate is provided. A remarkably expedient process for the simultaneous purification and concentration of the aqueous product stream relies on ion-pairing extraction for the removal of the water-soluble 1,1,3,3-tetramethylguanidine. Crystallization then affords 59-64% overall yield of the monosodium salt form of the product. 相似文献
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