title: Pyrazolone-quinazolone hybrids: a novel class of human 4-hydroxyphenylpyruvate dioxygenase inhibitors.
abstract: 4-Hydroxyphenylpyruvate dioxygenase (HPPD), converting 4-hydroxyphenylpyruvate acid to homogentisate, is an important target for treating type I tyrosinemia and alkaptonuria due to its significant role in tyrosine catabolism. However, only one commercial drug, NTBC, also known as nitisinone, has been available for clinical use so far. Herein, we have elucidated the structure-based design of a series of pyrazolone-quinazolone hybrids that are novel potent human HPPD inhibitors through the successful integration of various techniques including computational simulations, organic synthesis, and biochemical characterization. Most of the new compounds displayed potent inhibitory activity against the recombinant human HPPD in nanomolar range. Compounds 3h and 3u were identified as the most potent candidates with Ki values of around 10 nM against human HPPD, about three-fold more potent than NTBC. Molecular modeling indicated that the interaction between the pyrazolone ring and ferrous ion, and the hydrophobic interaction of quinazolone with its surrounding residues, such as Phe347 and Phe364, contributed greatly to the high potency of these inhibitors. Therefore, compounds 3h and 3u could be potentially useful for the treatment of type I tyrosinemia and other diseases with defects in tyrosine degradation.
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Xu
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
authors.forename: Hong-Yan
authors.initials: HY
authors.lastname: Lin
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
authors.forename: Run-Jie
authors.initials: RJ
authors.lastname: Cao
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
authors.forename: Ze-Zhong
authors.initials: ZZ
authors.lastname: Ming
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China. Electronic address: tomyang@mail.ccnu.edu.cn.
authors.forename: Wen-Chao
authors.initials: WC
authors.lastname: Yang
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 30071, PR China. Electronic address: gfyang@mail.ccnu.edu.cn.
authors.forename: Guang-Fu
authors.initials: GF
authors.lastname: Yang
mesh_terms: D015111:4-Hydroxyphenylpyruvate Dioxygenase / Q000037:antagonists & inhibitors* / Q000302:isolation & purification / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D062105:Molecular Docking Simulation; D015394:Molecular Structure; D047069:Pyrazolones / Q000737:chemistry / Q000494:pharmacology*; D011799:Quinazolines / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D004791:Enzyme Inhibitors; D047069:Pyrazolones; D011799:Quinazolines; C038362:pyrazolone; D015111:4-Hydroxyphenylpyruvate Dioxygenase
keywords: Human HPPD inhibitors; Pyrazolone; Quinazolones; Type I tyrosinemia