Facile synthesis of novel halogenated 4-pyrazolylspirocyclic-β-lactams: versatile heterocyclic synthons
| dc.contributor.author | Khullar, S. | |
| dc.contributor.author | Mandal, S. | |
| dc.date.accessioned | 2020-12-03T06:48:16Z | |
| dc.date.available | 2020-12-03T06:48:16Z | |
| dc.date.issued | 2016 | |
| dc.description | Only IISERM authors are available in the record. | |
| dc.description.abstract | A mild approach for the synthesis of halogenated 4-pyrazolylspirocyclic-β-lactams via halogen (I2, Br2, ICl) mediated intrasulfenyl cyclisation of cis-3-(prop-2′-ynyloxy)-4-pyrazolyl-β-lactams is described. The behaviour of the substrate towards the nature and variable amount of halogen was investigated. The structural and stereochemical analysis of novel β-lactams were carried out using FT-IR, NMR (1H and 13C), 2D-NMR (COSY and HSQC), elemental analysis (CHNS), mass spectrometry (EIMS) and single crystal X-ray crystallographic studies (3a, 6a, 7a). NMR experiments were also performed on cis-3-chloro-4-pyrazolyl-β-lactams to establish the relationship between isomeric ratio of rotamers and nature of solvents. The cis or trans configuration of the hydrogen/chloro/nucleophile substituent at C-3 was assigned with respect to C4-H. | en_US |
| dc.identifier.citation | Tetrahedron Letters, 57(25), pp.2822-2828. | en_US |
| dc.identifier.other | https://doi.org/10.1016/j.tetlet.2016.05.047 | |
| dc.identifier.uri | https://www.sciencedirect.com/science/article/pii/S0040403916305718 | |
| dc.identifier.uri | http://hdl.handle.net/123456789/2558 | |
| dc.language.iso | en | en_US |
| dc.publisher | Elsevier | en_US |
| dc.subject | β-Lactams | en_US |
| dc.subject | X-ray crystal structures | en_US |
| dc.subject | Halogenated | en_US |
| dc.subject | Rotamers | en_US |
| dc.subject | Spirocyclic | en_US |
| dc.title | Facile synthesis of novel halogenated 4-pyrazolylspirocyclic-β-lactams: versatile heterocyclic synthons | en_US |
| dc.type | Article | en_US |