{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T21:38:05Z","timestamp":1773437885481,"version":"3.50.1"},"reference-count":52,"publisher":"Oxford University Press (OUP)","issue":"D1","license":[{"start":{"date-parts":[[2021,10,29]],"date-time":"2021-10-29T00:00:00Z","timestamp":1635465600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22077087"],"award-info":[{"award-number":["22077087"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22074099"],"award-info":[{"award-number":["22074099"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,1,7]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Noncanonical nucleic acid structures, such as G-quadruplex (G4) and i-Motif (iM), have attracted increasing research interests because of their unique structural and binding properties, as well as their important biological activities. To date, thousands of small molecules that bind to varying G4\/iM structures have been designed, synthesized and tested for diverse chemical and biological uses. Because of the huge potential and increasing research interests on G4-targeting ligands, we launched the first G4 ligand database G4LDB in 2013. Here, we report a new version, termed G4LDB 2.2 (http:\/\/www.g4ldb.com), with upgrades in both content and function. Currently, G4LDB2.2 contains &amp;gt;3200 G4\/iM ligands, \u223c28\u00a0500 activity entries and 79 G4\u2013ligand docking models. In addition to G4 ligand library, we have also added a brand new iM ligand library to G4LDB 2.2, providing a comprehensive view of quadruplex nucleic acids. To further enhance user experience, we have also redesigned the user interface and optimized the database structure and retrieval mechanism. With these improvements, we anticipate that G4LDB 2.2 will serve as a comprehensive resource and useful research toolkit for researchers across wide scientific communities and accelerate discovering and validating better binders and drug candidates.<\/jats:p>","DOI":"10.1093\/nar\/gkab952","type":"journal-article","created":{"date-parts":[[2021,10,4]],"date-time":"2021-10-04T18:07:36Z","timestamp":1633370856000},"page":"D150-D160","source":"Crossref","is-referenced-by-count":76,"title":["G4LDB 2.2: a database for discovering and studying G-quadruplex and i-Motif ligands"],"prefix":"10.1093","volume":"50","author":[{"given":"Yu-Huan","family":"Wang","sequence":"first","affiliation":[{"name":"Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu610064, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1830-1154","authenticated-orcid":false,"given":"Qian-Fan","family":"Yang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu610064, China"}]},{"given":"Xiao","family":"Lin","sequence":"additional","affiliation":[{"name":"Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu610064, China"}]},{"given":"Die","family":"Chen","sequence":"additional","affiliation":[{"name":"West China School of Pharmacy, Sichuan University, Chengdu610041, China"}]},{"given":"Zhi-Yin","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu610064, China"}]},{"given":"Bin","family":"Chen","sequence":"additional","affiliation":[{"name":"Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu610064, China"}]},{"given":"Hua-Yi","family":"Han","sequence":"additional","affiliation":[{"name":"West China School of Pharmacy, Sichuan University, Chengdu610041, China"}]},{"given":"Hao-Di","family":"Chen","sequence":"additional","affiliation":[{"name":"Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu610064, China"}]},{"given":"Kai-Cong","family":"Cai","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Normal University, Fuzhou350007, China"}]},{"given":"Qian","family":"Li","sequence":"additional","affiliation":[{"name":"Beijing National Laboratory for Molecular Sciences (BNLMS), Center for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2639-4661","authenticated-orcid":false,"given":"Shu","family":"Yang","sequence":"additional","affiliation":[{"name":"West China School of Pharmacy, Sichuan University, Chengdu610041, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5325-2602","authenticated-orcid":false,"given":"Ya-Lin","family":"Tang","sequence":"additional","affiliation":[{"name":"Beijing National Laboratory for Molecular Sciences (BNLMS), Center for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2616-5343","authenticated-orcid":false,"given":"Feng","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu610064, China"}]}],"member":"286","published-online":{"date-parts":[[2021,10,29]]},"reference":[{"key":"2022010507425288200_B1","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1038\/nsb0294-83","article-title":"Human telomeric C-Strand tetraplexes","volume":"1","author":"Ahmed","year":"1994","journal-title":"Nat. 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