{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,27]],"date-time":"2026-10-27T09:33:51Z","timestamp":1793093631019,"version":"4.5.0"},"reference-count":39,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,4,25]],"date-time":"2019-04-25T00:00:00Z","timestamp":1556150400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Key Projects in the National Science &amp; Technological Pillar Program during the Twelfth Five-year Plan Period","award":["2015BAD11B01"],"award-info":[{"award-number":["2015BAD11B01"]}]},{"name":"The embarked fund for the China Agriculture Research System","award":["CARS-37"],"award-info":[{"award-number":["CARS-37"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>To combat bacterial resistance, a series of new oxazolidinone-fluoroquinolone hybrids have been synthesized and characterized. All synthetic hybrids were preliminarily evaluated for their in vitro antibacterial activities against 6 standard strains and 3 clinical isolates. The majority of hybrids displayed excellent activities against Gram-positive bacteria, but limited activities against Gram-negative bacteria. Hybrids OBP-4 and OBP-5 were found to be the most promising compounds. Further, in vitro antibacterial activities, mode of action and acute toxicity in mice of hybrids OBP-4 and OBP-5 were investigated. Hybrids OBP-4 and OBP-5 exhibited potent activities against Gram-positive bacteria, including drug-resistant strains. Correspondingly, studies on the mode of action of hybrids OBP-4 and OBP-5 indicated a strong inhibitory activity on protein synthesis by binding the active site of 50S subunit, but a weak inhibitory action on DNA synthesis. In addition, LD50 values of hybrids OBP-4 and OBP-5 in the acute oral toxicity were larger than 2000 mg\/kg, suggesting a good safety profile.<\/jats:p>","DOI":"10.3390\/molecules24081641","type":"journal-article","created":{"date-parts":[[2019,4,25]],"date-time":"2019-04-25T11:19:04Z","timestamp":1556191144000},"page":"1641","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Synthesis, Antibacterial Activities, Mode of Action and Acute Toxicity Studies of New Oxazolidinone-Fluoroquinolone Hybrids"],"prefix":"10.3390","volume":"24","author":[{"given":"Lili","family":"Liu","sequence":"first","affiliation":[{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug project of Gansu Province, Lanzhou 730050, China"},{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liping","family":"Shao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug project of Gansu Province, Lanzhou 730050, China"},{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jing","family":"Li","sequence":"additional","affiliation":[{"name":"R &amp; D Center, Beijing Orbiepharm Co., Ltd., Beijing 100085, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haifeng","family":"Cui","sequence":"additional","affiliation":[{"name":"R &amp; D Center, Beijing Orbiepharm Co., Ltd., Beijing 100085, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bing","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug project of Gansu Province, Lanzhou 730050, China"},{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuzheng","family":"Zhou","sequence":"additional","affiliation":[{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug project of Gansu Province, Lanzhou 730050, China"},{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pengyue","family":"Lv","sequence":"additional","affiliation":[{"name":"R &amp; D Center, Beijing Orbiepharm Co., Ltd., Beijing 100085, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiyu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou 730050, China"},{"name":"Key Laboratory of New Animal Drug project of Gansu Province, Lanzhou 730050, China"},{"name":"Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences (CAAS), Lanzhou 730050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,4,25]]},"reference":[{"key":"ref_1","first-page":"321","article-title":"Antibiotic use: Present and future","volume":"30","author":"Zinner","year":"2007","journal-title":"New Microbiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1002\/jor.23656","article-title":"Bacteria antibiotic resistance: New challenges and opportunities for implant-associated orthopedic infections","volume":"36","author":"Li","year":"2018","journal-title":"J. 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