Isoxazole-3-hydroxamic acid derivatives as peptide deformylase inhibitors and potential antibacterial agents

Synthesis of 3,4,5-Trisubstituted Isoxazoles through Gold-Catalyzed Cascade Cyclization-Oxidative Alkynylation and Cyclization-Fluorination of 2-Alkynone O-Methyloximes

“…With the desired (Z)-4-phenylbut-3-yn-2-one O-methyloxime (1a) in hand, we began to investigate various gold catalysts and combinations with silver salts: (PPh 3 )AuCl, (PCy 3 )AuCl, (PhO) 3 PAuCl, AuCl, AuCl 3 , (PPh 3 )AuNTf 2 , (IPr)AuCl (IPr = N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene), along with AgOTf, AgNTf2, or AgSbF6 (Table 1). To our delight, most Au catalysts produced cyclizationoxidative cross-coupling product 4a except (IPr)AuCl (Table 1, entry 18).…”

“…1 is an important scaffold frequently found in many natural products and biologically active compounds such as analgesics, 2 antibiotics, 3 antidepressants, 4 and anticancer agent. 5 It has also been used as a synthetic intermediate, building block and chiral ligand in organic synthesis.…”

The Reactivity of <i>Gem</i> Cyanoester Ketene Dithiolates towards the Development of Potent Antioxidant Heterocycles

“…The synthetic intermediates 2-(chloromethyl) benzoxazole (1) and 2-(chloromethyl)benzothiazole (2) were prepared by the irradiation of 2-aminophenol/2-aminothiophenol and chloroacetyl chloride for 10-15 min at a power of 500 W. 31,32) However, 2-(chloromethyl)-1H-benzimidazole (3) was obtained by treating o-phenylenediamine with chloroacetic acid in the presence of 5 N HCl. 33) A one pot reaction of ethyl cyanoacetate, carbon disulfide and 1/2/3 in the presence of K 2 In order to develop a new class of tris heterocyclic compounds, the gem cyanoester functionality in 4 was made to react with hydrazine hydrate in the presence of 1 eq of K 2 CO 3 in DMF. Instead of the expected tris heterocyclic compound, intramolecular cyclization of 4 occurred with the formation of a mixture of tetrasubstituted thiophene, ethyl 2-((benzo[d]-oxazol-2′-yl)methylthio)-4-amino-5-(benzo[d]oxazol-2-yl)thiophene-3-carboxylate (7) and 4-amino-2,5-di(benzo [d]oxazol-2′-yl)thieno [2,3-b]thiophen-3(2H)-one (10) in a ratio of 3 : 1.…”

“…Pyrazole and isoxazole derivatives are interesting heterocyclic compounds since they show a wide range of pharmacological properties including antiinflammatory, 1) antibacterial 2) and antifungal. 3) In addition pyrazoles and isoxazoles are present in leading pharmaceuticals viz., Celebrex, Viagra, Valdecoxib.…”

Mild and efficient oxidation of 2-pyrazolines and isoxazolines by trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxalane–NH4Cl–HOAc in water–MeCN

“…Isoxazolines and pyrazolines are interesting five-membered heterocyclic compounds because of their biological and pharmacological importance, for example as anticancer [1], anti-viral [2], anti-inflammatory [3], anti-diabetic [4], anti-bacterial [5], antimicrobial, and antifungal agents [6]. Several isoxazoles and pyrazoles have agrochemical herbicidal and soil fungicidal activity and act as pesticides and insecticides [7,8].…”