{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T11:52:44Z","timestamp":1768823564708,"version":"3.49.0"},"reference-count":98,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,10,25]],"date-time":"2019-10-25T00:00:00Z","timestamp":1571961600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/QEQ-MED\/7042\/2014"],"award-info":[{"award-number":["PTDC\/QEQ-MED\/7042\/2014"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UID\/DTP\/04138\/2019"],"award-info":[{"award-number":["UID\/DTP\/04138\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/104441\/2014"],"award-info":[{"award-number":["SFRH\/BD\/104441\/2014"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"European Structural &amp; Investment Funds through the COMPETE Programme under grant LISBOA-01-0145-FEDER-016405","award":["SAICTPAC\/0019\/2015"],"award-info":[{"award-number":["SAICTPAC\/0019\/2015"]}]},{"name":"PT2020 Programa Operacional do Centro 2020), and the financial support by FEDER (European Regional Development Fund) through the COMPETE 2020 Programme (Operational Programme for Competitiveness and Internationalization), project CENTRO-01-0247-FEDER-0032","award":["FEDER-003269"],"award-info":[{"award-number":["FEDER-003269"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Drug discovery now faces a new challenge, where the availability of experimental data is no longer the limiting step, and instead, making sense of the data has gained a new level of importance, propelled by the extensive incorporation of cheminformatics and bioinformatics methodologies into the drug discovery and development pipeline. These enable, for example, the inference of structure-activity relationships that can be useful in the discovery of new drug candidates. One of the therapeutic applications that could benefit from this type of data mining is proteasome inhibition, given that multiple compounds have been designed and tested for the last 20 years, and this collection of data is yet to be subjected to such type of assessment. This study presents a retrospective overview of two decades of proteasome inhibitors development (680 compounds), in order to gather what could be learned from them and apply this knowledge to any future drug discovery on this subject. Our analysis focused on how different chemical descriptors coupled with statistical tools can be used to extract interesting patterns of activity. Multiple instances of the structure-activity relationship were observed in this dataset, either for isolated molecular descriptors (e.g., molecular refractivity and topological polar surface area) as well as scaffold similarity or chemical space overlap. Building a decision tree allowed the identification of two meaningful decision rules that describe the chemical parameters associated with high activity. Additionally, a characterization of the prevalence of key functional groups gives insight into global patterns followed in drug discovery projects, and highlights some systematically underexplored parts of the chemical space. The various chemical patterns identified provided useful insight that can be applied in future drug discovery projects, and give an overview of what has been done so far.<\/jats:p>","DOI":"10.3390\/ijms20215326","type":"journal-article","created":{"date-parts":[[2019,10,25]],"date-time":"2019-10-25T11:05:18Z","timestamp":1572001518000},"page":"5326","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Chemical Patterns of Proteasome Inhibitors: Lessons Learned from Two Decades of Drug Design"],"prefix":"10.3390","volume":"20","author":[{"given":"Romina A.","family":"Guedes","sequence":"first","affiliation":[{"name":"iMed.Ulisboa and Faculdade de Farm\u00e1cia, Universidade de Lisboa, 1649-003 Lisbon, Portugal"},{"name":"Center for Neurosciences and Cell Biology, Universidade de Coimbra, 3004-504 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7039-0022","authenticated-orcid":false,"given":"Nat\u00e1lia","family":"Aniceto","sequence":"additional","affiliation":[{"name":"iMed.Ulisboa and Faculdade de Farm\u00e1cia, Universidade de Lisboa, 1649-003 Lisbon, Portugal"}]},{"given":"Marina A. P.","family":"Andrade","sequence":"additional","affiliation":[{"name":"ISCTE \u2013 Instituto Universit\u00e1rio de Lisboa\/ISTAR-IUL, 1649-026 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0779-6083","authenticated-orcid":false,"given":"Jorge A. R.","family":"Salvador","sequence":"additional","affiliation":[{"name":"Center for Neurosciences and Cell Biology, Universidade de Coimbra, 3004-504 Coimbra, Portugal"},{"name":"Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5790-9181","authenticated-orcid":false,"given":"Rita C.","family":"Guedes","sequence":"additional","affiliation":[{"name":"iMed.Ulisboa and Faculdade de Farm\u00e1cia, Universidade de Lisboa, 1649-003 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,25]]},"reference":[{"key":"ref_1","unstructured":"International Agency for Research on Cancer\u2014World Health Organization (2018). Latest Global Cancer Data: Cancer Burden Rises to 18.1 Million New Cases and 9.6 Million Cancer Deaths in 2018, World Health Organization. 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