<?xml version="1.0" encoding="UTF-8"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-10-23T14:57:00Z</responseDate><request verb="GetRecord" identifier="oai:gumushane-rdlopen.rawdatalibrary.net:gumushane/15562" metadataPrefix="oai_dc">https://gumushane-rdlopen.rawdatalibrary.net/oai/request</request><GetRecord><record><header><identifier>oai:gumushane-rdlopen.rawdatalibrary.net:gumushane/15562</identifier><datestamp>2026-10-22T11:37:59Z</datestamp><setSpec>openaire</setSpec><setSpec>com_gumushane_10000</setSpec><setSpec>col_gumushane_10001</setSpec><setSpec>com_gumushane_10007</setSpec><setSpec>col_gumushane_10180</setSpec></header><metadata><oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"><dc:title>New thiophene-1,2,4-triazole-5(3)-ones: Highly bioactive thiosemicarbazides, structures of Schiff bases and triazole-thiols</dc:title><dc:creator>Ünver, Yasemin</dc:creator><dc:creator>Sancak, Kemal</dc:creator><dc:creator>Çelik, Fatih</dc:creator><dc:creator>Birinci, Emrah</dc:creator><dc:creator>Küçük, Murat</dc:creator><dc:creator>Soylu, Serkan</dc:creator><dc:creator>Burnaz, Nesibe Arslan</dc:creator><dc:subject>1,2,4-Triazole/thiol</dc:subject><dc:subject>Antimicrobial</dc:subject><dc:subject>Antioxidant</dc:subject><dc:subject>Schiff base</dc:subject><dc:subject>Thiosemicarbazide</dc:subject><dc:description>Key compound 2-(4-amino-5-oxo-3-(thiophene-2-ylmethyl)-4,5-dihydro-1,2,4- tiazole-1-yl) acetohydrazide (3) was synthesized by reacting hydrazine hydrate with ethyl-2-(4-amino-5-oxo-3-(thiophene-2-ylmethyl)-4,5-dihydro-1,2,4-tiazole- 1yl)acetate (2), obtained in basic media from 4-amino-5-(thiophene-2-ylmethyl)- 2H-1,2,4-triazole-3(4H)-one (1). Compound 3 was converted to thiosemicarbazide derivatives (4a-d) and Schiff base derivatives 6a-e and 7a-e. The treatment of compound 4 with NaOH gave 4-amino-2-((4-(4-aryl)-5-mercapto-4H-1,2,4-triazole-3- yl)methyl)-5-(thiophene-2-ylmethyl)-2H-1,2,4-triazole-3(4H)-ones (5a-d). All newly compounds, well characterized by elemental analyses, IR, 1H NMR, 13C NMR and mass spectral studies were tested for their antioxidant and antimicrobial activities. Thiosemicarbazide derivatives (4a-d) were highly active in two antioxidant tests with 69.0-88.2% DPPH scavenging and 503-1257 μM TEAC values, while the others showed lower or no activity. The results of the two antioxidant tests correlated well. Moreover, Thiosemicarbazide derivatives (4a-d) also showed antibacterial activity against Staphylococcus aureus, Bacillus cereus, and Mycobacterium smegmatis. Thiosemicarbazide group deserves attention in the synthesis of bioactive compounds.</dc:description><dc:publisher>Elsevier Masson SAS</dc:publisher><dc:date>2014</dc:date><dc:type>Article</dc:type><dc:identifier>https://rdlopen.rawdatalibrary.net/r/gumushane/15562</dc:identifier><dc:identifier>https://doi.org/10.1016/j.ejmech.2014.01.014</dc:identifier><dc:identifier>0223-5234</dc:identifier><dc:language>en</dc:language><dc:relation>European Journal of Medicinal Chemistry</dc:relation><dc:rights>info:eu-repo/semantics/closedAccess</dc:rights><dc:type>info:eu-repo/semantics/article</dc:type><dc:identifier>https://gumushane-rdlopen.rawdatalibrary.net/tr/items/gumushane/15562</dc:identifier></oai_dc:dc></metadata></record></GetRecord></OAI-PMH>