Novel Synthesis of (<i>E</i>)-3-Arylidene-2,3-dihydrobenzo[<i>b</i>][1,4]oxazepin-4(5<i>H</i>)-ones Using Baylis–Hillman Derivatives via Reductive Cyclization
作者:Manickam Bakthadoss、Gandhi Murugan
DOI:10.1080/00397910802519166
日期:2009.3.10
Abstract A simple synthesis of novel (E)-3-arylidene-2,3-dihydrobenzo[b][1,4]oxazepin-4(5H)-ones from bromides of the Baylis--Hillman adducts using Fe/AcOH for the in situ reduction of nitro group, into an amino group, followed by the cyclization as a key step, has been described.
Synthesis of allylic thiocyanates and novel 1,3-thiazin-4-ones from 2-(bromomethyl)alkenoates and S-nucleophiles in aqueous medium
作者:Marcus M. Sá、Luciano Fernandes、Misael Ferreira、Adailton J. Bortoluzzi
DOI:10.1016/j.tetlet.2007.12.029
日期:2008.2
Allylic thiocyanates and novel heterocycles containing the 1,3-thiazin-4-one core are easily obtained in high yields and mild conditions by nucleophilic displacement of 2-(bromomethyl)alkenoates (derived from Morita–Baylis–Hillman adducts) with sulphur-centred nucleophiles in aqueous acetone at 25 °C. Treatment of allylic bromides with NaSCN gave the corresponding (Z)-2-(thiocyanomethyl)alkenoates
A facile route for the synthesis of 20 new 1,4-disubstituted tetrazolone derivatives from allyl bromides of Baylis-Hillman adducts and various 1-substituted tetrazolones is described. All the synthesized compounds were screened for in vitro antibacterial and antifungal activity. Out of 20 newly synthesized compounds 16 compounds showed very good activity against the Gram-positive bacteria Bacillus subtilis compare to the standard drug ciprofloxacin. The compounds 7b, 7n and 7o showed remarkable activity against both the Gram-positive bacteria B. subtilis and Staphylococcus aureus. Two compounds 7l and 7o showed very good activity against the Gram-negative bacteria Escherichia coli. The compounds, when tested for antifungal activity four compounds- 7b, 7l, 7o and 7s- showed very good activity against the strain Aspergillus niger, whereas seven compounds- 7e, 7g, 7h, 7l, 7o and 7s- display good activity against Candida albicans. Compounds 7b, 7e, 7g, 7l and 7o exhibited very good-to-high activity towards all the strains tested.