Synthesis, reactions, and antimicrobial evaluations of new benzo[e][1,3]thiazine derivatives

Abstract

4H-Spiro[benzo [d] [1,3]oxathiine-2,1′-cyclohexan]-4-one undergoes aminolysis with certain aromatic amines to give the respective 4-benzenesulfonamide, Ethyl benzoate, and 4-acetylphenyl of 4-oxospirobenzo[e][1,3]thiazine derivatives. The Schiff bases prepared by reacting Ethyl benzoate derivative 2a with aldehydes, undergoes cyclocondensation with thioglycolic acid yielding p-methoxyphenyl and 2-(thiophen-2-yl) thiazolidinone derivatives. Treatment of the benzoate derivative with hydrazine hydrate afforded the corresponding benzohydrazide derivative which upon reaction with phenyl isocyanate and phenyl isothiocyanate afforded the urea and thiourea derivatives. New pyrimidine, pyridone, and imino pyridine derivatives of 4-oxospirobenzo[e][1,3]thiazine were also successfully prepared by reacting 2b or 2c with the appropriate organic reagents. Structural elucidations for the new products were based upon compatible microanalytical and spectroscopic measurements. Besides, their biological screening indicated that they possess potent antimicrobial activity in comparison with reference drugs.

Updated Information on Antimicrobial Activity of Hydrazide–Hydrazones

“…The highest activity was shown by compound 22 (Figure 16, Table 9) [27]. The hydrazide-hydrazone 23 obtained by Ewies et al exhibited promising antibacterial activity against S. aureus, S. typhimurium, and P. aeruginosa (Figure 17, Table 10) [28]. In 2020, Popiołek et al reported the synthesis and antimicrobial activity potential of hydrazide-hydrazones of 5-nitrofuran-2-carboxylic acid.…”

Synthesis, characterization, docking studies and anti-inflammatory activity of new safe NSAIDs agent based on Ibuprofen phenylalanine derivatives

“…In continuation of synthesis of effective candidates in our laboratory as antimicrobial, antiviral, and anticancer agents [19][20][21][22][23]; we aim to conjugate Ibuprofen with phenyl alanine to be an effective agents as antiinflammatory and analgesic. Our strategy based on preparation of ibuprofen derivatives 1-17 starting from acid chloride 2 that may be expected to have biological activities (Scheme 1).…”

“…The carrageenan induced paw edema method used for evaluated the anti-inflammatory activity for 5 , 6 , 12 , 16 and 17 [21]. The compounds were examined at a 35 mg kg-1 body mass oral dosage and compared to the conventional medication ibuprofen at the same dose.…”

Transition‐Metal‐Free One‐Pot [3+3] Heteroannulative Coupling of Thioamides with Epichlorohydrin: Access to Diverse 1,3‐Thiazinanes

“…Among them, 1,3‐thiazine and their reduced forms dihydro‐1,3‐thiazine and tetrahydro‐1,3‐thiazine frameworks are privileged structural motifs found in many natural products [2] and biologically significant compounds [3] . For example, compounds containing such a skeleton exhibit antimicrobial, [3a] antibacterial, [3b,c] analgesic, [3d] antitumor, [3e] antihypertensive and NOS inhibiting activities [3f] . Moreover, well known antibiotics such as cephamycin and cephradine (cephalosporin class of β‐lactam antibiotics) contain 1,3‐thiazine scaffold (Figure 1).…”