{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Tong N"],"funding":["Eunice &amp; Milton H. Ring Charitable Foundation","National Cancer Institute","NCI NIH HHS","NIGMS NIH HHS","Duquesne University"],"pagination":["748-770"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC10186366"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["6(5)"],"pubmed_abstract":["Multitargeted agents with tumor selectivity result in reduced drug resistance and dose-limiting toxicities. We report 6-substituted thieno[2,3-<i>d</i>]pyrimidine compounds (<b>3</b>-<b>9</b>) with pyridine (<b>3</b>, <b>4</b>), fluorine-substituted pyridine (<b>5</b>), phenyl (<b>6</b>, <b>7</b>), and thiophene side chains (<b>8</b>, <b>9</b>), for comparison with unsubstituted phenyl (<b>1</b>, <b>2</b>) and thiophene side chain (<b>10</b>, <b>11</b>) containing thieno[2,3-<i>d</i>]pyrimidine compounds. Compounds <b>3</b>-<b>9</b> inhibited proliferation of Chinese hamster ovary cells (CHO) expressing folate receptors (FRs) α or β but not the reduced folate carrier (RFC); modest inhibition of CHO cells expressing the proton-coupled folate transporter (PCFT) by <b>4</b>, <b>5</b>, <b>6</b>, and <b>9</b> was observed. Replacement of the side-chain 1',4'-phenyl ring with 2',5'-pyridyl, or 2',5'-pyridyl with a fluorine insertion ortho to l-glutamate resulted in increased potency toward FR-expressing CHO cells. Toward KB tumor cells, <b>4</b>-<b>9</b> were highly active (IC<sub>50</sub>'s from 2.11 to 7.19 nM). By metabolite rescue in KB cells and <i>in vitro</i> enzyme assays, <i>de novo</i> purine biosynthesis was identified as a targeted pathway (at 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase (AICARFTase) and glycinamide ribonucleotide formyltransferase (GARFTase)). Compound <b>9</b> was 17- to 882-fold more potent than previously reported compounds <b>2</b>, <b>10</b>, and <b>11</b> against GARFTase. By targeted metabolomics and metabolite rescue, <b>1</b>, <b>2</b>, and <b>6</b> also inhibited mitochondrial serine hydroxymethyl transferase 2 (SHMT2); enzyme assays confirmed inhibition of SHMT2. X-ray crystallographic structures were obtained for <b>4</b>, <b>5</b>, <b>9</b>, and <b>10</b> with human GARFTase. This series affords an exciting new structural platform for potent multitargeted antitumor agents with FR transport selectivity."],"journal":["ACS pharmacology & translational science"],"pubmed_title":["Multitargeted 6-Substituted Thieno[2,3-<i>d</i>]pyrimidines as Folate Receptor-Selective Anticancer Agents that Inhibit Cytosolic and Mitochondrial One-Carbon Metabolism."],"pmcid":["PMC10186366"],"funding_grant_id":["R01 CA053535","F31 CA243215","P30 CA022453","P30 CA22453","R01 CA250469","P41 GM103311","R01 CA166711","R01 CA53535","P30 GM124169","T32 CA009531","T32 GM131994"],"pubmed_authors":["Hou Z","Li J","Tong N","Katinas JM","Bao X","Schneider M","Dann CE","Wong-Roushar J","Nyman MC","Kim S","Wallace-Povirk A","O'Connor C","Gangjee A","Matherly LH","Shah Y"],"additional_accession":[]},"is_claimable":false,"name":"Multitargeted 6-Substituted Thieno[2,3-<i>d</i>]pyrimidines as Folate Receptor-Selective Anticancer Agents that Inhibit Cytosolic and Mitochondrial One-Carbon Metabolism.","description":"Multitargeted agents with tumor selectivity result in reduced drug resistance and dose-limiting toxicities. We report 6-substituted thieno[2,3-<i>d</i>]pyrimidine compounds (<b>3</b>-<b>9</b>) with pyridine (<b>3</b>, <b>4</b>), fluorine-substituted pyridine (<b>5</b>), phenyl (<b>6</b>, <b>7</b>), and thiophene side chains (<b>8</b>, <b>9</b>), for comparison with unsubstituted phenyl (<b>1</b>, <b>2</b>) and thiophene side chain (<b>10</b>, <b>11</b>) containing thieno[2,3-<i>d</i>]pyrimidine compounds. Compounds <b>3</b>-<b>9</b> inhibited proliferation of Chinese hamster ovary cells (CHO) expressing folate receptors (FRs) α or β but not the reduced folate carrier (RFC); modest inhibition of CHO cells expressing the proton-coupled folate transporter (PCFT) by <b>4</b>, <b>5</b>, <b>6</b>, and <b>9</b> was observed. Replacement of the side-chain 1',4'-phenyl ring with 2',5'-pyridyl, or 2',5'-pyridyl with a fluorine insertion ortho to l-glutamate resulted in increased potency toward FR-expressing CHO cells. Toward KB tumor cells, <b>4</b>-<b>9</b> were highly active (IC<sub>50</sub>'s from 2.11 to 7.19 nM). By metabolite rescue in KB cells and <i>in vitro</i> enzyme assays, <i>de novo</i> purine biosynthesis was identified as a targeted pathway (at 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase (AICARFTase) and glycinamide ribonucleotide formyltransferase (GARFTase)). Compound <b>9</b> was 17- to 882-fold more potent than previously reported compounds <b>2</b>, <b>10</b>, and <b>11</b> against GARFTase. By targeted metabolomics and metabolite rescue, <b>1</b>, <b>2</b>, and <b>6</b> also inhibited mitochondrial serine hydroxymethyl transferase 2 (SHMT2); enzyme assays confirmed inhibition of SHMT2. X-ray crystallographic structures were obtained for <b>4</b>, <b>5</b>, <b>9</b>, and <b>10</b> with human GARFTase. This series affords an exciting new structural platform for potent multitargeted antitumor agents with FR transport selectivity.","dates":{"release":"2023-01-01T00:00:00Z","publication":"2023 May","modification":"2026-06-03T03:57:53.867Z","creation":"2026-04-24T03:09:45.16Z"},"accession":"S-EPMC10186366","cross_references":{"pubmed":["37200803"],"doi":["10.1021/acsptsci.3c00020"]}}