{"doi":"10.1248/cpb.38.2926","title":"Quinazolin-2-ones having a spirohydantoin ring. I. Synthesis of spiro(1,2,3,4-tetrahydroquinazoline-4,4'-imidazolidine)-2,2',5'-trione by reaction of 1-carbamoylisatin with urea or guanidine.","abstract":null,"journal":"Chemical and Pharmaceutical Bulletin","year":1990,"id":661995,"datarank":0.3453877639491069,"base_score":2.302585092994046,"endowment":2.302585092994046,"self_citation_contribution":0.3453877639491069,"citation_network_contribution":0.0,"self_endowment_contribution":0.3453877639491069,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":9,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1728215,"name":"Ken-ichi OZAKI","orcid":null,"position":1,"is_corresponding":false},{"id":1728216,"name":"Hiroshi OHMIZU","orcid":null,"position":2,"is_corresponding":false},{"id":1728217,"name":"Yoshihisa YAMADA","orcid":null,"position":3,"is_corresponding":false},{"id":1717063,"name":"Mamoru SUZUKI","orcid":null,"position":4,"is_corresponding":false},{"id":1728214,"name":"Masafumi YAMAGISHI","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Quinazolin-2-ones having a spirohydantoin ring. I. Synthesis of spiro(1,2,3,4-tetrahydroquinazoline-4,4'-imidazolidine)-2,2',5'-trione by reaction of 1-carbamoylisatin with urea or guanidine.","abstract":"Reaction of 1-methylcarbamoylisation (4) with urea in the presence of 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU) gave 4-hydroxy-3-methyl-4-ureidocarbonyl-1, 2, 3, 4-tetrahydroquinazolin-2-one (5), which was easily cyclized with 10% HCl to afford a spirohydantoin derivative; 3-methyl-spiro[1, 2, 3, 4-tetrahydroquinazoline-4, 4'-imidazolidine]-2, 2', 5'-trione (6). In a similar manner, 2'-imino-3-methyl-spiro[1, 2, 3, 4-tetrahydroquinazoline-4.4'-imidazolidine]-2, 5'-dione (8) was prepared by the reaction of 4 with guanidine, and 8 was further converted to the spirohydantoin compound 6 by treatment with sodium nitrite in acetic acid.","is_dataset_classified":null,"base_score":2.302585092994046,"endowment":2.302585092994046,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"19965766","pmcid":null,"openalex_id":"https://openalex.org/W2081634466","authors":[],"funders":[],"total_grants":0,"fwci":0.467,"citation_percentile":0.61782146,"influential_citations":0,"citation_trend":[{"year":2014,"count":1},{"year":2019,"count":1},{"year":2022,"count":1}],"oa_status":"bronze","license":null,"oa_locations":[{"url":"https://www.jstage.jst.go.jp/article/cpb1958/38/11/38_11_2926/_pdf","host_type":"journal"},{"url":"https://www.jstage.jst.go.jp/article/cpb1958/38/11/38_11_2926/_pdf","host_type":"publisher"},{"url":"http://www.jstage.jst.go.jp/article/cpb1958/38/11/38_11_2926/_pdf","host_type":"publisher"},{"url":"https://doi.org/10.1248/cpb.38.2926","host_type":"journal"}],"fields_of_study":["Quinazolinone synthesis and applications","Synthesis of heterocyclic compounds","Synthesis and Characterization of Heterocyclic Compounds"],"mesh_terms":[],"keywords":["Imidazolidine","Chemistry","Guanidine","Urea","Acetic acid","Sodium nitrite","Hydantoin","Ring (chemistry)","Derivative (finance)","Medicinal chemistry","Organic chemistry"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Clean water and sanitation"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-12T12:11:54.912063Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}