title: Synthesis, biological, and antitumor activity of a highly potent 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolate inhibitor with proton-coupled folate transporter and folate receptor selectivity over the reduced folate carrier that inhibits β-glycinamide ribonucleotide formyltransferase.
abstract: 2-Amino-4-oxo-6-substituted pyrrolo[2,3-d]pyrimidine antifolates with a thienoyl side chain (compounds 1-3, respectively) were synthesized for comparison with compound 4, the previous lead compound of this series. Conversion of hydroxyl acetylen-thiophene carboxylic esters to thiophenyl-α-bromomethylketones and condensation with 2,4-diamino-6-hydroxypyrimidine afforded the 6-substituted pyrrolo[2,3-d]pyrimidine compounds of type 18 and 19. Coupling with l-glutamate diethyl ester, followed by saponification, afforded 1-3. Compound 3 selectively inhibited the proliferation of cells expressing folate receptors (FRs) α or β, or the proton-coupled folate transporter (PCFT), including KB and IGROV1 human tumor cells, much more potently than 4. Compound 3 was more inhibitory than 4 toward β-glycinamide ribonucleotide formyltransferase (GARFTase). Both 3 and 4 depleted cellular ATP pools. In SCID mice with IGROV1 tumors, 3 was more efficacious than 4. Collectively, our results show potent antitumor activity for 3 in vitro and in vivo, associated with its selective membrane transport by FRs and PCFT over RFC and inhibition of GARFTase, clearly establishing the 3-atom bridge as superior to the 1-, 2-, and 4-atom bridge lengths for the activity of this series.
authors: Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh 15219, Pennsylvania 15282, United States.
authors: Lei
authors: L
authors: Wang
authors: Sita Kugel
authors: SK
authors: Desmoulin
authors: Christina
authors: C
authors: Cherian
authors: Lisa
authors: L
authors: Polin
authors: Kathryn
authors: K
authors: White
authors: Juiwanna
authors: J
authors: Kushner
authors: Andreas
authors: A
authors: Fulterer
authors: Min-Hwang
authors: MH
authors: Chang
authors: Shermaine
authors: S
authors: Mitchell-Ryan
authors: Mark
authors: M
authors: Stout
authors: Michael F
authors: MF
authors: Romero
authors: Zhanjun
authors: Z
authors: Hou
authors: Larry H
authors: LH
authors: Matherly
authors: Aleem
authors: A
authors: Gangjee
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D005260:Female; D058975:Folate Receptor 1 / Q000378:metabolism*; D058976:Folate Receptor 2 / Q000378:metabolism*; D005493:Folic Acid Antagonists / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D005971:Glutamates / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D009368:Neoplasm Transplantation; D009865:Oocytes / Q000187:drug effects / Q000502:physiology; D018408:Patch-Clamp Techniques; D051026:Phosphoribosylglycinamide Formyltransferase / Q000037:antagonists & inhibitors*; D058979:Proton-Coupled Folate Transporter / Q000378:metabolism*; D011743:Pyrimidines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D011744:Pyrimidinones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D058978:Reduced Folate Carrier Protein / Q000378:metabolism*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014183:Transplantation, Heterologous; D014981:Xenopus
chemical_list: D000970:Antineoplastic Agents; D058975:Folate Receptor 1; D058976:Folate Receptor 2; D005493:Folic Acid Antagonists; D005971:Glutamates; C568952:N-((5-((2-amino-4-oxo-4,7-dihydro-3H-pyrrolo(2,3-d)pyrimidin-6-yl)propyl)thiophen-2-yl)carbonyl)glutamic acid; D058979:Proton-Coupled Folate Transporter; D011743:Pyrimidines; D011744:Pyrimidinones; D058978:Reduced Folate Carrier Protein; D000255:Adenosine Triphosphate; D051026:Phosphoribosylglycinamide Formyltransferase