nComplexes of Crotonaldehyde and N-Benzaldehyde salycylhydrazone with some transition metals and their antimicrobial studies

nComplexes of Crotonaldehyde and N-Benzaldehyde salycylhydrazone with some transition metals and their antimicrobial studies | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article nComplexes of Crotonaldehyde and N-Benzaldehyde salycylhydrazone with some transition metals and their antimicrobial studies Adewumi Ezekiel Alamuoye, Stella Adedunni Emmanuel, Thomson Izuagie, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9085855/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 15 You are reading this latest preprint version Abstract Complexes of Ni(II), Cu(II), Co(II), Mn(II), and Fe(II) with crotonaldehyde- and N-benzaldehyde-salicylhydrazone (CSH/NBSH) were synthesized and characterized by FTIR, UV–Vis spectroscopy, conductivity, melting point, magnetic moment, and XRD. FTIR indicates tridentate coordination via carbonyl-O, azomethine-N, and amine-N, while electronic spectra and magnetic moments support predominantly octahedral geometries. XRD (Scherrer) reveals nanocrystallites spanning ~ 20–41 nm with dominant reflections at 2θ ≈ 20–29° (d ≈ 4.4–3.1 Å) and low-to-moderate crystallinity (~ 3–33%), with Mn derivatives showing the highest crystalline fractions and Ni derivatives the largest coherent domains. Consistent with these structural features – defect-rich surfaces and accessible metal centers – the metal chelates exhibit enhanced antibacterial activity relative to the free ligands: activity increases are most notable against Staphylococcus aureus and Pseudomonas aeruginosa , whereas responses against Proteus vulgaris , Klebsiella spp., Salmonella Typhi, Escherichia coli , Streptococcus spp., and Bacillus cereus are comparatively weaker. These results highlight a structure–activity relationship in which nanoscale domain size and crystallinity modulate antimicrobial performance, offering levers for tuning future ligand/metal choices. Metal Complexes Crotoaldehyde N-benzaldehyde Microorganisms activities Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 13 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviewers agreed at journal 04 Apr, 2026 Reviews received at journal 03 Apr, 2026 Reviewers agreed at journal 03 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers invited by journal 02 Apr, 2026 Editor invited by journal 02 Apr, 2026 Editor assigned by journal 20 Mar, 2026 Submission checks completed at journal 20 Mar, 2026 First submitted to journal 10 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9085855","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":618358921,"identity":"82e13c24-a2ca-4e15-a66d-9460d0af0815","order_by":0,"name":"Adewumi Ezekiel Alamuoye","email":"","orcid":"","institution":"University of Abuja","correspondingAuthor":false,"prefix":"","firstName":"Adewumi","middleName":"Ezekiel","lastName":"Alamuoye","suffix":""},{"id":618358923,"identity":"072775fc-c36a-4e05-bdab-f58fd016847c","order_by":1,"name":"Stella Adedunni 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their antimicrobial studies","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-chemistry","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ccjo","sideBox":"Learn more about [BMC Chemistry](https://bmcchem.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ccjo/default.aspx","title":"BMC Chemistry","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Metal Complexes, Crotoaldehyde, N-benzaldehyde, Microorganisms activities","lastPublishedDoi":"10.21203/rs.3.rs-9085855/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9085855/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eComplexes of Ni(II), Cu(II), Co(II), Mn(II), and Fe(II) with crotonaldehyde- and N-benzaldehyde-salicylhydrazone (CSH/NBSH) were synthesized and characterized by FTIR, UV\u0026ndash;Vis spectroscopy, conductivity, melting point, magnetic moment, and XRD. FTIR indicates tridentate coordination via carbonyl-O, azomethine-N, and amine-N, while electronic spectra and magnetic moments support predominantly octahedral geometries. XRD (Scherrer) reveals nanocrystallites spanning\u0026thinsp;~\u0026thinsp;20\u0026ndash;41 nm with dominant reflections at 2θ\u0026thinsp;\u0026asymp;\u0026thinsp;20\u0026ndash;29\u0026deg; (d\u0026thinsp;\u0026asymp;\u0026thinsp;4.4\u0026ndash;3.1 \u0026Aring;) and low-to-moderate crystallinity (~\u0026thinsp;3\u0026ndash;33%), with Mn derivatives showing the highest crystalline fractions and Ni derivatives the largest coherent domains. Consistent with these structural features \u0026ndash; defect-rich surfaces and accessible metal centers \u0026ndash; the metal chelates exhibit enhanced antibacterial activity relative to the free ligands: activity increases are most notable against \u003cem\u003eStaphylococcus aureus\u003c/em\u003e and \u003cem\u003ePseudomonas aeruginosa\u003c/em\u003e, whereas responses against \u003cem\u003eProteus vulgaris\u003c/em\u003e, \u003cem\u003eKlebsiella\u003c/em\u003e spp., \u003cem\u003eSalmonella\u003c/em\u003e Typhi, \u003cem\u003eEscherichia coli\u003c/em\u003e, \u003cem\u003eStreptococcus\u003c/em\u003e spp., and \u003cem\u003eBacillus cereus\u003c/em\u003e are comparatively weaker. These results highlight a structure\u0026ndash;activity relationship in which nanoscale domain size and crystallinity modulate antimicrobial performance, offering levers for tuning future ligand/metal choices.\u003c/p\u003e","manuscriptTitle":"nComplexes of Crotonaldehyde and N-Benzaldehyde salycylhydrazone with some transition metals and their antimicrobial studies","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-08 18:37:04","doi":"10.21203/rs.3.rs-9085855/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-13T12:03:56+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T18:24:25+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T15:53:36+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T05:48:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"168384447847609529984211020131040031572","date":"2026-04-04T15:58:06+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-04T02:24:09+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"4863167864652372498508785519145787755","date":"2026-04-03T13:25:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"249072071637606906090860377181934581332","date":"2026-04-02T19:16:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"185941021167477909182484409722195241869","date":"2026-04-02T11:06:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"317631379463997250784372524888231420927","date":"2026-04-02T10:36:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-02T10:04:12+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-02T08:07:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-20T08:26:43+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-20T08:26:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Chemistry","date":"2026-03-10T15:31:38+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-chemistry","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ccjo","sideBox":"Learn more about [BMC Chemistry](https://bmcchem.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ccjo/default.aspx","title":"BMC Chemistry","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"46558028-1bca-482e-8d5e-048cc3562e35","owner":[],"postedDate":"April 8th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-04-13T12:11:45+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-08 18:37:04","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9085855","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9085855","identity":"rs-9085855","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}