{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T17:42:08Z","timestamp":1770745328908,"version":"3.49.0"},"reference-count":58,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T00:00:00Z","timestamp":1769817600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100017242","name":"National Institutes for Food and Drug Control","doi-asserted-by":"publisher","award":["2025HYZX11"],"award-info":[{"award-number":["2025HYZX11"]}],"id":[{"id":"10.13039\/100017242","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Crystal structures of 4-(trifluoromethyl)benzene-1-carbohydrazide (1), 4-(trifluoromethyl)-N\u2019-{[4-(trifluoromethyl)phenyl]carbonyl}benzohydrazide (2) and (1R,2S,6R,7S,8S,10R)-4-({[4-(trifluoromethyl)phenyl]carbonyl}amino)-4-azatetracyclo [5.3.2.08,10.02,6]dodec-11-ene-3,5-dione (3) were first reported. Besides the three new single-crystal structures, the single-crystal structure of tecovirimat (4) was also described herein. Hirshfeld analysis quantified intermolecular interactions, and PXRD confirmed high crystal phase purity. DSC data and packing energy calculations demonstrated that the melting point order matched the magnitude of packing energies for compounds with similar structures and analogous intermolecular interactions. According to the ICH M7 guidelines, in silico genotoxicity assessment using Derek Nexus and Sarah Nexus indicated that 2 showed no structural alerts for genotoxicity (ICH M7 Class 5), whereas 1 and 3 were classified as ICH M7 Class 3 due to structural features associated with potential genotoxicity, warranting further experimental evaluation.<\/jats:p>","DOI":"10.3390\/molecules31030502","type":"journal-article","created":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T15:38:12Z","timestamp":1770046692000},"page":"502","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Tecovirimat-Related Substance: Characterization, Hirshfeld Analysis, Theoretical Study, In Silico Toxicity Assessment"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-3830-9831","authenticated-orcid":false,"given":"Fengfeng","family":"Wang","sequence":"first","affiliation":[{"name":"Institute for Chemical Drug Control, National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0835-2476","authenticated-orcid":false,"given":"Xiaowen","family":"Hu","sequence":"additional","affiliation":[{"name":"Institute for Chemical Drug Control, National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9416-8650","authenticated-orcid":false,"given":"Caiyu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute for Chemical Drug Control, National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lin","family":"Luan","sequence":"additional","affiliation":[{"name":"Institute for Chemical Drug Control, National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8130-2793","authenticated-orcid":false,"given":"Zhengzheng","family":"Zhou","sequence":"additional","affiliation":[{"name":"NMPA Key Laboratory for Safety Evaluation of Cosmetics, Department of Hygiene Inspection & Quarantine Science, School of Public Health, Southern Medical University, Guangzhou 510515, China"},{"name":"Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Hygiene Inspection & Quarantine Science, School of Public Health, Southern Medical University, Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7714-9194","authenticated-orcid":false,"given":"Yang","family":"Liu","sequence":"additional","affiliation":[{"name":"Institute for Chemical Drug Control, National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"653","DOI":"10.2217\/fvl.11.27","article-title":"Development of the Small-Molecule Antiviral ST-246\u00ae as a Smallpox Therapeutic","volume":"6","author":"Grosenbach","year":"2011","journal-title":"Future Virol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"6246","DOI":"10.1128\/AAC.00977-13","article-title":"Efficacy of Tecovirimat (ST-246) in Nonhuman Primates Infected with Variola Virus (Smallpox)","volume":"57","author":"Mucker","year":"2013","journal-title":"Antimicrob. 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