62838-24-8

Upstream product

• 17240-30-1 2-phenylbenzo[d][1,3]thiazine-4-thione 
• 118-92-3 anthranilic acid 
• 2227-79-4 benzenecarbothioamide 
• 7510-49-8 methyl 2-(benzamido)benzoate 
• 2454-39-9 2-aminobenzothioamide 
• 98-88-4 benzoyl chloride 
• 100698-06-4 2-mercapto-2-thioxo-2,3-dihydro-1H-2λ⁵-benzo[1,3,2]diazaphosphinine-4-thione pyridinium salt 
• 59525-06-3 2-benzoylaminothiobenzamide 
• 108-24-7 acetic anhydride 

Downstream Products

• 83389-98-4 (4-Oxo-2-phenyl-4H-quinazolin-3-yl)-carbamic acid methyl ester 
• 28005-51-8 methyl 2-(thio-p-toluoylamino)benzoate 

Relevant academic research and scientific papers

A metal-A nd base-free domino protocol for the synthesis of 1,3-benzoselenazines, 1,3-benzothiazines and related scaffolds

Efficient protocols have been described for the synthesis of 1,3-benzoselenazines, 1,3-benzothiazines, 2-aryl thiazin-4-ones and diaryl[b,f][1,5]diazocine-6,12(5H,11H)-diones. These transformations were successfully driven towards the product formation under mild acid catalyzed reaction conditions at room temperature using 2-amino aryl/hetero-aryl alkyl alcohols and amides as substrates. The merits of the present methods also rely on the easy access of rarely explored bioactive scaffolds like 1,3-benzoselenazine derivatives, for which well-documented methods are rarely known in the literature. A broad range of substrates with both electron-rich and electron-deficient groups were well-tolerated under the developed conditions to furnish the desired products in yields up to 98%. The scope of the devised method is not only restricted to the synthesis of 1,3-benzoselenazines, but it was also further extended towards the synthesis of 1,3-benzothiazines, 1,3-benzothiazinones and the corresponding eight membered N-heterocycles such as diaryl[b,f][1,5]diazocine-6,12(5H,11H)-diones.

Synthesis of substituted 2-benzoylaminothiobenzamides and their ring closure to substituted 2-phenylquinazoline-4-thiones

Acylation of 2-aminothiobenzamide or 2-methylaminothiobenzamide with substituted benzoyl chlorides has been used to synthesise the corresponding 2-benzoyl-aminothiobenzamides whose subsequent sodium methoxide-catalysed ring closure gives the corresponding quinazoline-4-thiones. These compounds were characterised by means of their 1H- and 13C-NMR spectra. The preferred tautomeric form of selected compounds has been discussed on the basis of their 13C-NMR, IR and Raman spectra. It has been found that in the given medium 1-methyl-quinazoline-4-thiones undergo a replacement of the sulphur substituent by oxygen giving 1-methyl-quinazoline-4-ones. In strong acid media, 2-benzoylaminothiobenzamide is cyclised through its sulphur atom to give 2-phenylbenzo[d-1,3]thiazin-4-one.