摘要：
4-Hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) has been recognized as one of the most promising targets in the field of herbicide innovation considering the severity of weed resistance currently. In a persistent effort to develop effective HPPD-inhibiting herbicides, a structure-guided strategy was carried out to perform the structural optimization for triketone-quinazoline-2,4-diones, a novel HPPD inhibitor scaffold first discovered in our lab. Herein, starting from the crystal structure of Arabidopsis thaliana (At)HPPD complexed with 6-(2-hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,5-dimethyl-3-(o-tolyl)quinazoline-2,4(1H,3H)-dione (MBQ), three subseries of quinazoline-2,4-dione derivatives were designed and prepared by optimizing the hydrophobic interactions between the side chain of the core structure at the R(1) position and the hydrophobic pocket at the active site entrance of AtHPPD. 6-(2-Hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,5-dimethyl-3-(3-(trimethylsilyl)prop-2-yn-1-yl)quinazoline-2,4(1H,3H)-dione (60) with the best inhibitory activity against AtHPPD was identified to be the first subnanomolar-range AtHPPD inhibitor (K(i) = 0.86 nM), which significantly outperformed that of the lead compound MBQ (K(i) = 8.2 nM). Further determination of the crystal structure of AtHPPD in complex with compound 60 (1.85 Å) and the binding energy calculation provided a molecular basis for the understanding of its high efficiency. Additionally, the greenhouse assay indicated that 6-(2-hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,5-dimethyl-3-propylquinazoline-2,4(1H,3H)-dione (28) and compound 60 showed acceptable crop safety against peanut and good herbicidal activity with a broad spectrum. Moreover, compound 28 also showed superior selectivity for wheat at the dosage of 120 g ai/ha and favorable herbicidal efficacy toward the gramineous weeds at the dosage of as low as 30 g ai/ha. We believe that compounds 28 and 60 have promising prospects as new herbicide candidates for wheat and peanut fields.
摘要：
4-Hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) has been identified as one of the most significant targets in herbicide discovery for resistant weed control. In a continuing effort to discover potent novel HPPD inhibitors, we adopted a ring-expansion strategy to design a series of novel pyrazole-quinazoline-2,4-dione hybrids based on the previously discovered pyrazole-isoindoline-1,3-dione scaffold. One compound, 3-(2-chlorophenyl)-6-(5-hydroxy-1,3-dimethyl-1H-pyrazole-4-carbonyl)1,5-dimethylquinazoline-2,4(1H,3H)-dione (9bj), displayed excellent potency against AtHPPD, with an IC50 value of 84 nM, which is approximately 16-fold more potent than pyrasulfotole (IC50 = 1359 nM) and 2.7-fold more potent than mesotrione (IC50 = 226 nM). Furthermore, the co-crystal structure of the AtHPPD-9bj complex (PDB ID 6LGT) was determined at a resolution of 1.75 angstrom. Similar to the existing HPPD inhibitors, compound 9bj formed a bidentate chelating interaction with the metal ion and a pi-pi stacking interaction with Phe381 and Phe424. In contrast, o-chlorophenyl at the N3 position of quinazoline-2,4-dione with a double conformation was surrounded by hydrophobic residues (Met335, Leu368, Leu427, Phe424, Phe392, and Phe381). Remarkably, the greenhouse assay indicated that most compounds displayed excellent herbicidal activity (complete inhibition) against at least one of the tested weeds at the application rate of 150 g of active ingredient (ai)/ha. Most promisingly, compounds 9aj and 9bi not only exhibited prominent weed control effects with a broad spectrum but also showed very good crop safety to cotton, peanuts, and corn at the dose of 150 g of ai/ha.
作者机构：
[Chen Qiong; Cai Zhuomei; Liu Yuchao; Yang Jingfang; Qu Renyu; Yang Guangfu] Cent China Normal Univ, Int Joint Res Ctr Intelligent Biosensor Technol &, Coll Chem, Key Lab Pesticide & Chem Biol,Minist Educ, Wuhan 430079, Peoples R China.;[Niu Congwei; Xi Zhen] Nankai Univ, State Key Lab Elementoorgan Chem, Tianjin 300071, Peoples R China.
通讯机构：
[Yang Guangfu] C;Cent China Normal Univ, Int Joint Res Ctr Intelligent Biosensor Technol &, Coll Chem, Key Lab Pesticide & Chem Biol,Minist Educ, Wuhan 430079, Peoples R China.
关键词：
乙酰羟酸合成酶;P197L突变体;反抗性;构象柔性;抗性杂草
摘要：
为寻找新型乙酰羟酸合成酶（EC2.2.1.6,AHAS）抑制剂以克服由靶标突变（P197L突变）所引起的杂草抗性问题,利用"构象柔性度分析"策略设计、合成了一系列烷氧基取代的嘧啶水杨酸衍生物.其中, 9个化合物对P197L突变型AHAS的抗性倍数（RF值）均小于等于1,在酶水平上具有良好的反抗性.特别是2-（（4,6-二甲氧基嘧啶-2-基）氧基）-6-（2-氟乙氧基）苯甲酸（5l）,被进一步确定为该系列最有效的反抗性AHAS抑制剂（RF=0.31）,不仅与氯磺隆（RF=2060）和双草醚（RF=4.57）相比抗性程度大幅降低,并且对野生型At AHAS和P197L突变体的抑制活性均达到了亚微摩尔水平,优于双草醚.此外,在150gai/ha的施用剂量下,2-（（4,6-二甲氧基嘧啶-2-基）氧基）-6-（2-（甲氧基）乙氧基）苯甲酸（5a）、2-（（4,6-二甲氧基嘧啶-2-基）氧基）-6-（3-（甲氧基）丙氧基）苯甲酸（5f）、2-（（4,6-二甲氧基嘧啶-2-基）氧基）-6-（2-氟乙氧基）苯甲酸（5l）和2-（（4,6-二甲氧基嘧啶-2-基）氧基）-6-（2,2-二氟乙氧基）苯甲酸（5m）对敏感型和抗性（P197L-AHAS）播娘蒿同时表现出优异的除草活性.值得注意的是,即使在最低剂量37.5 g ai/ha下,化合物5l对这两种杂草的除草防效仍超过85%,表现出良好的活体反抗性,具有深入研究的价值.
摘要：
BACKGROUND Intensifying weed resistance has challenged the use of existing acetohydroxyacid synthase (AHAS)-inhibiting herbicides. Hence, there is currently an urgent requirement for the discovery of a new AHAS inhibitor to effectively control AHAS herbicide-resistant weed species produced by target mutation. RESULTS To combat weed resistance caused by AHAS with P197L mutation, we built a structure library consisting of pyrimidinyl-salicylic acid derivatives. Using the pharmacophore-linked fragment virtual screening (PFVS) approach, hit compound 8 bearing 6-phenoxymethyl substituent was identified as a potential AHAS inhibitor with antiresistance effect. Subsequently, derivatives of compound 8 were synthesized and evaluated for their inhibitory activities. The study of the enzyme-based structure-activity relationship and structure-resistance relationship studies led to the discovery of a qualified candidate, 28. This compound not only significantly inhibited the activity of wild-type Arabidopsis thaliana (At) AHAS and P197L mutant, but also exhibited good antiresistance properties (RF = 0.79). Notably, compared with bispyribac at 37.5-150 g of active ingredient per hectare (g a.i. ha(-1)), compound 27 exhibited higher growth inhibition against both sensitive and resistant Descurainia sophia, CONCLUSION The title compounds have great potential to be developed as new leads to effectively control herbicide-resistant weeds comprising AHAS with P197L mutation. Also, our study provided a positive case for discovering novel, potent and antiresistance inhibitors using a fragment-based drug design approach. (c) 2020 Society of Chemical Industry
摘要：
The discovery of 4-hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) inhibitors has been an active area of research due to their great potential as herbicides for weed control. Starting from the binding mode of known inhibitors of HPPD, a series of HPPD inhibitors with new molecular scaffolds were designed and synthesized by hybridizing 2-benzoylethen-1-ol and isoindoline-1,3-dione fragments. The results of the in vitro tests indicated that the newly synthesized compounds showed good HPPD inhibitory activity with IC50 values against the recombinant Arabidopsis thaliana HPPD (AtHPPD) ranging from 0.0039 mu M to over 1 mu M. Most promisingly, compound 4ae, 2-benzyl-5-(5-hydroxy-1,3-dimethyl-1H-pyrazole-4-carbonyl)isoindoline-1,3-dione, showed the highest AtHPPD inhibitory activity with a K-i value of 3.92 nM, making it approximately 10 times more potent than pyrasulfotole (K-i = 44 nM) and slightly more potent than mesotrione (K-i = 4.56 nM). In addition, the cocrystal structure of the AtHPPD-4ae complex was successfully resolved at a resolution of 1.8 angstrom. The X-ray diffraction analysis indicated that the two carbonyl groups of 2-benzoylethen-l-ol formed a bidentate chelating interaction with the metal ion, while the isoindoline-1,3-dione moiety formed pronounced pi-pi stacking interactions with Phe381 and Phe424. Moreover, water-mediated hydrogen bonding interactions were observed between Asn282 and the nitrogen atoms of the pyrazole ring of 4ae. The above results showed that the pyrazole-isoindoline-1,3-dione hybrid is a promising scaffold for developing HPPD inhibitors.
作者机构：
[Chen Qiong; Yang Guangfu; Yang Jingfang; Qu Renyu; Yan Yaochao] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Chen, Q; Yang, GF] C;Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Wuhan 430079, Hubei, Peoples R China.
关键词：
乙酰羟酸合成酶;反抗性;P197L突变体;构象柔性;抗性杂草
摘要：
乙酰羟酸合成酶(Acetohydroxyacid synthase, AHAS)是一类重要的除草剂靶标,但是靶向AHAS的抑制剂是所有除草剂类型中抗性最为严重的一类,因此设计具有反抗性的AHAS抑制剂显得尤为必要.本工作基于前期低抗性AHAS抑制剂结构,利用“构象柔性度分析”的设计策略合理增加分子柔性,设计并合成了13个含“双氧桥”结构的嘧啶水杨酸类抑制剂.目标分子均经过氢谱(~1H NMR)、碳谱(~(13)C NMR)和高分辨质谱(HRMS)确证.酶水平活性结果显示,部分化合物对P197L突变体表现出了微摩尔水平的抑制作用,特别是2-((4,6-二甲氧基嘧啶-2-基)氧基)-6-(2-氟-4-硝基苯氧基)-4-甲基苯甲酸(61)对P197L突变体表现出了良好的反抗性.盆栽除草活性结果表明,个别化合物对抗性杂草播娘蒿具有一定的除草活性,其中2-((4,6-二甲氧基嘧啶-2-基)氧基)-6-(2-氟苯氧基)-4-甲基苯甲酸(6b)在150 g ai/ha浓度下,对敏感生物型播娘蒿和抗性播娘蒿均达到80%的除草防效,具有进一步深入研究的价值.
作者：
Qu Renyu;Liu Yuchao;Wishwajith, W. M.;Kandegama, W.;Qiong, Chen*;...
期刊：
MINI-REVIEWS IN MEDICINAL CHEMISTRY,2018年18(9):781-793 ISSN：1389-5575
通讯作者：
Qiong, Chen
作者机构：
[Qiong, Chen; Liu Yuchao; Wishwajith, W. M.; Kandegama, W.; Qu Renyu; Yang Guangfu] Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.;[Qiong, Chen] Cent China Normal Univ, Coll Chem, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Qiong, Chen] C;Cent China Normal Univ, Coll Chem, Wuhan 430079, Hubei, Peoples R China.
摘要：
The triazolopyrimidine ring is a ubiquitous structural feature of many active compounds with diversified pharmacology efficacy. These structures have aroused our / researchers interests in the development of novel compounds with anticancer, anti-inflammatory, antibacterial, antifungal, and other activities. A large number of published literatures were reviewed during the last few decades. This review contains various pharmacological and agrochemical activities of triazolopyrimidine and it may be regarded as the lead compound for the new research towards future medicinal and agrochemical development.
摘要：
Tuning the binding selectivity through appropriate ways is a primary goal in the design and optimization of a lead toward agrochemical discovery. However, how to achieve rational design of selectivity is still a big challenge. Herein, we developed a novel computational fragment generation and coupling (CFGC) strategy that led to a series of highly potent and bioselective inhibitors targeting protoporphyrinogen IX oxidase. This enzyme plays a vital role in heme and chlorophyll biosynthesis, which has been proven to be associated with many drugs and agrochemicals. However, existing agrochemicals are nonbioselective, resulting in a great threat to nontargeted organisms. To the best of our knowledge, this is the first bioselective inhibitor targeting the tetrapyrrole biosynthesis pathway. In addition, the candidate showed excellent in vivo bioactivity and much better safety toward humans.
作者机构：
[Boussouar, Imene; Li, Haibing; Zhang, Fan; Tian, Demei; Chen, Xue] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol CCNU, Minist Educ, Wuhan 430079, Peoples R China.;[Zhang, Yulun; White, Henry S.; Chen, Qianjin] Univ Utah, Dept Chem, 315 S,1400 E, Salt Lake City, UT 84112 USA.
通讯机构：
[Li, Haibing] C;Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol CCNU, Minist Educ, Wuhan 430079, Peoples R China.
摘要：
Functionalized 6-arylsalicylate substructures occur in a variety of pharmacologically relevant natural products and bioactive compounds. Especially 6-arylsubstituted salicylates, as a key pharmacophore of anti-resistant acetohydroxyacid synthase (AHAS) inhibitors have played a lead role in combatting the weed-resistance issues. Previously, we have explored two new methods to synthesize position-6 aryl substituted salicylic acid fragment. However, these two methods failed to introduce various substituents into salicylic acid. Here an efficient method for the synthesis of 6-substituted salicylates is described via a microwave-promoted Suzuki cross-coupling. Due to the obvious advantages of this method, such as a wide range of substrates, smooth and rapid reaction and moderate to excellent yields, this protocol could be utilized to synthesize more anti-resistant AHAS inhibitors.
作者机构：
[Wu, Qiong-You; Yang, Guang-Fu; Zhang, Hu; Liu, Peng-Fei; Chen, Qiong; Zhoua, Shao-Lin] Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.;[Clough, John; Seville, Anne; Gu, Yu-Cheng] Syngenta Jealotts Hill Int Res Ctr, Bracknell RG42 6EY, Berks, England.
通讯机构：
[Yang, Guang-Fu] C;Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.
摘要：
The synthesis of albucidin and its enantiomer are described. It involves a visible-light photocatalysis deiodination at the late stage. The absolute configuration of natural albucidin is determined as (1R,3S). This work provides a basis for structural modification to develop a new type of herbicidal from an old structure.
通讯机构：
[Hao, GF; Yang, GF; Yang, Guang-Fu] C;Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.;Collaborat Innovat Ctr Chem Sci & Engn, Tianjin 300072, Peoples R China.
摘要：
N-Quinolyl biaryl carboxamides have received tremendous attention for their notable biological properties. Here we have described a general protocol for the preparation of N-quinolyl 3′/4′-biaryl carboxamides by microwave-assisted Suzuki–Miyaura cross-coupling reaction and N-Boc deprotection in one pot. This method, which did not require acids, was used to produce a series of N-quinolyl 3′/4′-biaryl carboxamides with excellent functional group tolerance and high yields (70% to 95%).
