Oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corre...Oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corresponding imidazolone derivatives 3-8, respectively. Moreover, oxazolone 2 reacted with some heterocyclic amines in glacial acetic acid giving the corresponding imidazolone derivatives 9-14, respectively. Cyclocondensation of thiosemicarbazide with compound 2 in dry pyridine afforded compound 15. Addition of secondary amines to olefin double bond of compound 2 gave the corresponding addition products 16-19, respectively. Michael addition of compound 2 with some active methylene compounds afforded oxazolone derivatives 20-23, respectively. These prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil and compounds 6a-e, 10 and 15 exhibited the highest antioxidant and anticorrosive activities. The effect of concentration of additives was studied to recommend the optimum concentration to be used. The results showed, for additive 15, 0.1 g for 1 L oil was the more effective concentration. Measurements for thermal analysis and of surface tension of oil after oxidation were also carried out.展开更多
Oxazolones are structural subunits in numerous natural products and designed molecules with substantial pharmacological properties.Here,a palladium-catalyzed chemodivergent regio-and enantioselective allylic alkylatio...Oxazolones are structural subunits in numerous natural products and designed molecules with substantial pharmacological properties.Here,a palladium-catalyzed chemodivergent regio-and enantioselective allylic alkylation of 4-or 5-substituted oxazol-2(3H)-ones with Morita-Baylis-Hillman(MBH)adducts has been developed using a spiroketal-based diphosphine as the ligand(50 examples).Interestingly,4-substituted oxazol-2(3H)-ones acted as a C-nucleophiles in the reaction to afford a range of chiral 4,5-substituted oxazol-2(3H)-ones in high yields(72-99%)with good to excellent chemo-,regio-,and enantioselectivities(C/N 95:5->99:1,b/l 91:9->99:1,85-98%ee).When a N-nucleophile was used under otherwise identical conditions,5-substituted oxazol-2(3H)-ones delivered a range of chiral 3,5-substituted oxazol-2(3H)-ones in high yields(68-98%)with good regio-and enantioselectivities(b/l 71:29-91:9,66-94%ee).The synthesis can be readily performed on gram scale under fairly low catalyst loadings,and the utility of the protocol was showcased in the facile transformation of the products into more elaborate chiral molecules.展开更多
In view of potent antimicrobial and anti-inflammatory activities exhibited by S-substituted imidazolones, a variety of novel imidazolone analogs 3a-I were synthesized by the condensation of different substituted oxazo...In view of potent antimicrobial and anti-inflammatory activities exhibited by S-substituted imidazolones, a variety of novel imidazolone analogs 3a-I were synthesized by the condensation of different substituted oxazolones I with various aromatic amines 2. All the synthesized compounds were screened for in vitro activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Several analogs produced good or moderate activities particularly against the tested Gram-positive bacteria Micrococcus luteus and Gram-negative bacteria Pseudornonas aeruginosa and, Meanwhile, compounds 3b and 3c displayed marked antifungal activity against C. albicans. In addition, the in vivo anti-inflammatory activity of the synthesized compounds was determined using the carrageenin-induced paw oedema method in rats. Two of S-substituted imidazo/one derivatives, 3k and 3d show good anti-inflammatory activity. The structures of all the newly svnthesized compounds were elucidated using IR, 1H NMR and 13C NMR.展开更多
Inflammatory bowel disease(IBD),the most important being Crohn's disease and ulcerative colitis,results from chronic dysregulation of the mucosal immune system in the gastrointestinal tract.Although the pathogenes...Inflammatory bowel disease(IBD),the most important being Crohn's disease and ulcerative colitis,results from chronic dysregulation of the mucosal immune system in the gastrointestinal tract.Although the pathogenesis of IBD remains unclear,it is widely accepted that genetic,environmental,and immunological factors are involved.Recent studies suggest that intestinal epithelial defenses are important to prevent inflammation by protecting against microbial pathogens and oxidative stresses.To investigate the etiology of IBD,animal models of experimental colitis have been developed and are frequently used to evaluate new anti-inflammatory treatments for IBD.Several models of experimental colitis that demonstrate various pathophysiological aspects of the human disease have been described.In this manuscript,we review the characteristic features of IBD through a discussion of the various chemically induced experimental models of colitis(e.g.dextran sodium sulfate-,2,4,6-trinitrobenzene sulfonic acid-,oxazolone-,acetic acid-,and indomethacin-induced models).We also summarize some regulatory and pathogenic factors demonstrated by these models that can,hopefully,be exploited to develop future therapeutic strategies against IBD.展开更多
This research the preventive effect of Kudingcha polyphenols(Kp)on colitis based on animal experiments.Experimental mice divided into four groups,including normal group,model group,low-concentration Kp(LKP)group and h...This research the preventive effect of Kudingcha polyphenols(Kp)on colitis based on animal experiments.Experimental mice divided into four groups,including normal group,model group,low-concentration Kp(LKP)group and high-concentration Kp(HKP)group,and they all smeared and given 0.15 mL 1%oxazolone solution by lavage to induce BALB/c mice colitis.DAI,colon weight/length ratio,serum levels of cytokines,related antioxidant activities of colon tissues such,and the mRNA expressions.The experimental results show that KP can significantly(p<0.05)reduce DAI in mice with colitis and inhibit shortening of colon caused by colitis,increase colon weight/length ratio.It can also significantly reduce(p<0.05)the activities of MPO,NO,MDA in mice colon tissues with colitis,increase the activity of GSH,and significantly increase(p<0.05)the level of IL-2 and decrease the level of IL-10 in mice serum with colitis.The results of qPCR assay show that Kp can significantly increase(p<0.05)the expression of Cu/Zn-SOD,Mn-SOD,GSH-Px,CAT,c-Kit,SCF and decrease the expression of IL-8,CXCR2 in mice colon tissues with colitis.Kp has a good preventive effect on colitis,and high concentration of PT has better preventive effect.展开更多
文摘Oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corresponding imidazolone derivatives 3-8, respectively. Moreover, oxazolone 2 reacted with some heterocyclic amines in glacial acetic acid giving the corresponding imidazolone derivatives 9-14, respectively. Cyclocondensation of thiosemicarbazide with compound 2 in dry pyridine afforded compound 15. Addition of secondary amines to olefin double bond of compound 2 gave the corresponding addition products 16-19, respectively. Michael addition of compound 2 with some active methylene compounds afforded oxazolone derivatives 20-23, respectively. These prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil and compounds 6a-e, 10 and 15 exhibited the highest antioxidant and anticorrosive activities. The effect of concentration of additives was studied to recommend the optimum concentration to be used. The results showed, for additive 15, 0.1 g for 1 L oil was the more effective concentration. Measurements for thermal analysis and of surface tension of oil after oxidation were also carried out.
基金financial supports from the National Key R&D Program of China(grant nos.2022YFA1503702 and 2021YFF0701602)NSFC(grant nos.22231011 and 22271303).
文摘Oxazolones are structural subunits in numerous natural products and designed molecules with substantial pharmacological properties.Here,a palladium-catalyzed chemodivergent regio-and enantioselective allylic alkylation of 4-or 5-substituted oxazol-2(3H)-ones with Morita-Baylis-Hillman(MBH)adducts has been developed using a spiroketal-based diphosphine as the ligand(50 examples).Interestingly,4-substituted oxazol-2(3H)-ones acted as a C-nucleophiles in the reaction to afford a range of chiral 4,5-substituted oxazol-2(3H)-ones in high yields(72-99%)with good to excellent chemo-,regio-,and enantioselectivities(C/N 95:5->99:1,b/l 91:9->99:1,85-98%ee).When a N-nucleophile was used under otherwise identical conditions,5-substituted oxazol-2(3H)-ones delivered a range of chiral 3,5-substituted oxazol-2(3H)-ones in high yields(68-98%)with good regio-and enantioselectivities(b/l 71:29-91:9,66-94%ee).The synthesis can be readily performed on gram scale under fairly low catalyst loadings,and the utility of the protocol was showcased in the facile transformation of the products into more elaborate chiral molecules.
文摘In view of potent antimicrobial and anti-inflammatory activities exhibited by S-substituted imidazolones, a variety of novel imidazolone analogs 3a-I were synthesized by the condensation of different substituted oxazolones I with various aromatic amines 2. All the synthesized compounds were screened for in vitro activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Several analogs produced good or moderate activities particularly against the tested Gram-positive bacteria Micrococcus luteus and Gram-negative bacteria Pseudornonas aeruginosa and, Meanwhile, compounds 3b and 3c displayed marked antifungal activity against C. albicans. In addition, the in vivo anti-inflammatory activity of the synthesized compounds was determined using the carrageenin-induced paw oedema method in rats. Two of S-substituted imidazo/one derivatives, 3k and 3d show good anti-inflammatory activity. The structures of all the newly svnthesized compounds were elucidated using IR, 1H NMR and 13C NMR.
基金National Institute of Health grants,No. DK64289,DK74454,and DK43351),IBD grants from the Eli and Edythe Broad Medical Foundation
文摘Inflammatory bowel disease(IBD),the most important being Crohn's disease and ulcerative colitis,results from chronic dysregulation of the mucosal immune system in the gastrointestinal tract.Although the pathogenesis of IBD remains unclear,it is widely accepted that genetic,environmental,and immunological factors are involved.Recent studies suggest that intestinal epithelial defenses are important to prevent inflammation by protecting against microbial pathogens and oxidative stresses.To investigate the etiology of IBD,animal models of experimental colitis have been developed and are frequently used to evaluate new anti-inflammatory treatments for IBD.Several models of experimental colitis that demonstrate various pathophysiological aspects of the human disease have been described.In this manuscript,we review the characteristic features of IBD through a discussion of the various chemically induced experimental models of colitis(e.g.dextran sodium sulfate-,2,4,6-trinitrobenzene sulfonic acid-,oxazolone-,acetic acid-,and indomethacin-induced models).We also summarize some regulatory and pathogenic factors demonstrated by these models that can,hopefully,be exploited to develop future therapeutic strategies against IBD.
基金The present research was supported by the Program for Innovation Team Building at Institutions of Higher Education in Chongqing(CXTDX201601040)the Introduction of High-level Personnel Research Start-up Fund of Chongqing University of Education(2013BSRC001),China.
文摘This research the preventive effect of Kudingcha polyphenols(Kp)on colitis based on animal experiments.Experimental mice divided into four groups,including normal group,model group,low-concentration Kp(LKP)group and high-concentration Kp(HKP)group,and they all smeared and given 0.15 mL 1%oxazolone solution by lavage to induce BALB/c mice colitis.DAI,colon weight/length ratio,serum levels of cytokines,related antioxidant activities of colon tissues such,and the mRNA expressions.The experimental results show that KP can significantly(p<0.05)reduce DAI in mice with colitis and inhibit shortening of colon caused by colitis,increase colon weight/length ratio.It can also significantly reduce(p<0.05)the activities of MPO,NO,MDA in mice colon tissues with colitis,increase the activity of GSH,and significantly increase(p<0.05)the level of IL-2 and decrease the level of IL-10 in mice serum with colitis.The results of qPCR assay show that Kp can significantly increase(p<0.05)the expression of Cu/Zn-SOD,Mn-SOD,GSH-Px,CAT,c-Kit,SCF and decrease the expression of IL-8,CXCR2 in mice colon tissues with colitis.Kp has a good preventive effect on colitis,and high concentration of PT has better preventive effect.
