Design and synthesis of pyrrolo[3,2-d]pyrimidine HER2/EGFR dual inhibitors: improvement of the physicochemical and pharmacokinetic profiles for potent in vivo anti-tumor efficacy.

During the course of our studies on a novel HER2/EGFR dual inhibitor (TAK-285), we found an alternative potent pyrrolo[3,2-d]pyrimidine compound (1a). To enhance the pharmacokinetic (PK) profile of this compound, we conducted chemical modifications into its N-5 side chain and conversion of the chemically modified compounds into their salts. Among them, 2cb, the tosylate salt of compound 2c, showed potent HER2/EGFR kinase inhibitory activity (IC(50): 11/11 nM) and cellular growth inhibitory activity (BT-474 cell GI(50): 56 nM) with a good drug metabolism and PK (DMPK) profile.

Design and synthesis of novel human epidermal growth factor receptor 2 (HER2)/epidermal growth factor receptor (EGFR) dual inhibitors bearing a pyrrolo[3,2-d]pyrimidine scaffold.

Dual inhibitors of human epidermal growth factor receptor 2 (HER2) and epidermal growth factor receptor (EGFR) have been investigated for breast, lung, gastric, prostate, and other cancers; one, lapatinib, is currently approved for breast cancer. To develop novel HER2/EGFR dual kinase inhibitors, we designed and synthesized pyrrolo[3,2-d]pyrimidine derivatives capable of fitting into the receptors' ATP binding site. Among the prepared compounds, 34e showed potent HER2 and EGFR (HER1) inhibitory activities as well as tumor growth inhibitory activity.

N-phenyl-N'-[4-(5H-pyrrolo[3,2-d]pyrimidin-4-yloxy)phenyl]ureas as novel inhibitors of VEGFR and FGFR kinases.

We have recently reported the discovery of pyrrolo[3,2-d]pyrimidine derivatives 1a and 1b as potent triple inhibitors of vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and Tie-2 kinases. To identify compounds having strong inhibitory activity against fibroblast growth factor receptor (FGFR) kinase, further modification was conducted using the co-crystal structure analysis of VEGFR2 and 1b. Among the compounds synthesized, urea derivative 11l having a piperazine moiety on the terminal benzene ring showed strong inhibitory activity against FGFR1 kinase as well as VEGFR2 kinase.

Design, synthesis, and evaluation of 5-methyl-4-phenoxy-5H-pyrrolo[3,2-d]pyrimidine derivatives: novel VEGFR2 kinase inhibitors binding to inactive kinase conformation.

We synthesized a series of pyrrolo[3,2-d]pyrimidine derivatives and evaluated their application as type-II inhibitors of vascular endothelial growth factor receptor 2 (VEGFR2) kinase. Incorporation of a diphenylurea moiety at the C4-position of the pyrrolo[3,2-d]pyrimidine core via an oxygen linker resulted in compounds that were potent inhibitors of VEGFR2 kinase. Of these derivatives, compound 20d showed the strongest inhibition of VEGF-stimulated proliferation of human umbilical vein endothelial cells (HUVEC).

Synthesis and anti-Helicobacter pylori activity of pyloricidin derivatives II. The combination of amino acid residues in the dipeptidic moiety and its effect on the anti-Helicobacter pylori activity.

The novel natural antibiotics pyloricidin A, B and C, consisting of a common (2S,3R,4R,5S)-5-amino-2,3,4,6-tetrahydroxyhexanoyl-beta-D-phenylalanine moiety and a terminal peptidic moiety (pyloricidin A: L-valine-L-valine-L-leucine; pyloricidin B: L-valine-L-leucine; pyloricidin C: L-leucine), exhibit potent and highly selective anti-Helicobacter pylori activity. In order to develop more potent compounds and to investigate structure activity relationships for the peptidic moiety with regard to the combination of amino acids, a series of derivatives with various dipeptidic moieties were prepared and evaluated for their anti-H. pylori activity.

Synthesis and anti-Helicobacter pylori activity of pyloricidin derivatives I. Structure-activity relationships on the terminal peptidic moiety.

The novel natural antibiotics pyloricidin A, B and C possess potent and highly selective antibacterial activity against Helicobacter pylori. In order to investigate the structure activity relationships for the terminal peptidic moiety, a series of pyloricidin B and pyloricidin C derivatives, bearing various amino acids in the moiety, were prepared and evaluated for their anti-H. pylori activity.

Total synthesis of novel antibiotics pyloricidin A, B and C and their application in the study of pyloricidin derivatives.

The novel natural antibiotics pyloricidin A, B and C, which possess potent and highly selective anti-Helicobacter pylori activity, were synthesized from D-galactosamine as a chiral template for the common (2S,3R,4R,5S)-5-amino-2,3,4,6-tetrahydroxyhexanoic acid moiety. The synthetic strategy, using 2-amino-2-deoxyuronic acid derivatives as key intermediates, was also useful to prepare a series of derivatives modified at the beta-D-phenylalanine and with altered stereochemistry on the 5-amino-2,3,4,6-tetrahydroxyhexanoic acid moiety. From the drastic decrease of their anti-H.