{
  "abstract": "Dihydropyrimidines (DPs) show a wide range of biological activities for medicinal applications. Among DP derivatives, 2-aryl-DPs have been reported to show remarkable pharmacological properties. In this work, 6-unsubstituted, N-unsubstituted 2-aryl-1,4-DP and its 1,6-DP tautomer were synthesized using a Pd2dba3/(2-furyl)3P-catalyzed, CuCl-mediated 2-arylation and a deprotection reaction. The sequential reactions give twenty types of the 1,4-DP and the 1,6-DP tautomers in high yields. To clarify the effects of substituents on their tautomeric behavior, 1H-NMR analysis of a mixture of the tautomers was performed. The analysis revealed that not only the electronic properties of substituents at the 2-position of 1,6-DP but also the electronic properties of substituents at the 4-position of 1,4-DP affect the stability of 1,4-DP and 1,6-DP. These compounds were also assessed for their antiproliferative effect on a human promyelocytic leukemia cell line, HL-60. Five compounds showed relatively high inhibitory activity, and their IC50 values were 1.7–3.9 μM. The analysis indicates that the 2-aryl group with a para-substituent and the cyclohexyl group are related to the biological activity.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "Yoshio Nishimura"
    },
    {
      "name": "Keito Taira"
    },
    {
      "name": "Yusuke Yamamoto"
    },
    {
      "name": "Hidetomo Kikuchi"
    },
    {
      "name": "Rie Arai"
    },
    {
      "name": "Yuki Toguchi"
    },
    {
      "name": "Bo Yuan"
    },
    {
      "name": "Katsuyoshi Sunaga"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/afkvfpzk014d9.bib",
  "cited_by": 0,
  "doi": "10.1248/cpb.c26-00391",
  "fulltext_url": "https://www.jstage.jst.go.jp/article/cpb/74/9/74_c26-00391/_article",
  "id": "afkvfpzk014d9",
  "issns": [
    "1347-5223",
    "0009-2363"
  ],
  "landing_url": "https://www.jstage.jst.go.jp/article/cpb/74/9/74_c26-00391/_article",
  "language": null,
  "licence": "CC-BY-NC",
  "licence_label": "CC BY-NC",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "jstage-journal",
      "chemistry/medicinal"
    ],
    [
      "openalex",
      "1605|Synthesis and biological activity"
    ]
  ],
  "openalex": "W7214214745",
  "pdf_url": "https://www.jstage.jst.go.jp/article/cpb/74/9/74_c26-00391/_pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-25",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/afkvfpzk014d9.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:34Z",
      "native_id": "10.1248/cpb.c26-00391",
      "source": "jstage",
      "url": "https://www.jstage.jst.go.jp/article/cpb/74/9/74_c26-00391/_article"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1605|Synthesis and biological activity",
      "subfield": "organic"
    }
  ],
  "title": "Synthesis, Tautomeric Behavior, and Biological Activity of 6-Unsubstituted 2-Aryl-1,4-dihydropyrimidines and 4-Unsubstituted 2-Aryl-1,6-dihydropyrimidines",
  "title_text": "Synthesis, Tautomeric Behavior, and Biological Activity of 6-Unsubstituted 2-Aryl-1,4-dihydropyrimidines and 4-Unsubstituted 2-Aryl-1,6-dihydropyrimidines",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:34Z",
  "url": "https://research.draconitic.com/paper/afkvfpzk014d9",
  "venue": "Chemical and Pharmaceutical Bulletin",
  "versions": []
}