Identification and Optimization of Novel Pyrimido-Isoxazolidine and Oxazine as Selective Hydride Donors
IR@CDRI: CSIR-Central Drug Research Institute, Lucknow
View Archive Info| Field | Value | |
| Creator |
Khan, I A
Balaramnavar, V M Saxena, A K |
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| Date |
2013-02-05T09:25:32Z
2013-02-05T09:25:32Z 2012 |
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| Identifier |
Tetrahedron 2012, 68, (49), 10122–10129
http://hdl.handle.net/123456789/994 |
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| Description |
Two novel carbon skeletons (3S,3a'R)-6'-(methylthio)-5',7a'-dihydro-1'H-spiro[indoline-3,3'-isoxazolo[3,4-d]pyrimidine]-2,4'(3a'H)-dione(11a) and 3-(methylthio)- 4a,5,7,11c-tetrahydropyrimido [4',5':3,4][1,2] oxazino [6,5-b]indol-1(2H)-one (12a) are characterized as hydride donors . The generation of these hydride sources during the spiroannulation reaction between isatin (4) and pyrimidine (5) through the free radical mechanism, was confirmed by (i) the increase in the stoichiometric yields of 11 and 12 when the same reaction was carried out in the presence of free radical initiators (e.g. mCPBA) and (ii) the formation of oxazepine (14) when AIBN was used as free radical initiator. The PKIE [KH/KD] values 4.5 and 4.9 obtained when deutrated 11a (d) was used in the presence of TFA and TFA-d, respectively suggest the hydride transfer step to be the rate determining step. These hydrides donors selectively reduce aldehyde in the presence of other reducible groups
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949129 bytes
application/pdf |
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| Language |
en
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| Relation |
CDRI communication no. 8329
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| Subject |
Hydride
Pyrimidine Isoxazolidine Oxazine Free radical |
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| Title |
Identification and Optimization of Novel Pyrimido-Isoxazolidine and Oxazine as Selective Hydride Donors
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Image
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