中间体2-氯-4-氟-5-硝基苯甲酸的新合成方法

探索中间体2-氯-4-氟-5-硝基苯甲酸的新合成方法。从4-氟苯胺出发,经过盐酸-双氧水体系氯化、重氮化、氰化、硝化-水解串联反应共4步得到2-氯-4-氟-5-硝基苯甲酸,纯度96.2%,总收率59.2%。新合成方法原材料易得、条件温和,具有工业化应用前景。

20%苯嘧磺草胺悬浮剂对高粱田一年生阔叶杂草的防效研究

高粱田的阔叶杂草对除草剂的抗性日趋严重,而能够用于高粱田的除草剂品种有限,导致阔叶杂草的防除比较困难,高粱的产量也受到了巨大影响。因此,生产中迫切需要筛选出对抗性阔叶杂草防效较好的除草剂。试验探讨了不同剂量20%苯嘧磺草胺悬浮剂对高粱田阔叶杂草苯氏蓼、反枝苋和藜的防效。结果表明,中高剂量(60、90 g a.i./hm^(2))20%苯嘧磺草胺悬浮剂对高粱田阔叶杂草防除效果较好,对阔叶杂草的鲜重防效最高可达97.75%,持效期可达30 d左右,并且对高粱安全,不影响产量,具有减施增效的特点。该试验结果能够为高粱田阔叶杂草的合理防除提供理论依据。

苯嘧磺草胺和精草铵膦对非耕地杂草的联合作用

明确苯嘧磺草胺和精草铵膦混用对非耕地杂草的联合作用,为2者混用提供科学依据。在温室条件下,采用整株生物测定法测定了2种除草剂混配对小飞蓬、龙葵、牛筋草和马唐的茎叶除草活性,用Gowing法评价了混用后的联合作用效果。结果表明,苯嘧磺草胺与精草铵膦混用防除小飞蓬、龙葵、牛筋草和马唐,联合作用表现为相加作用或增效作用,其中对龙葵、牛筋草和马唐的联合作用表现为增效作用的混配比为1∶2、1∶4、1∶8,且1∶4的组合数最多。苯嘧磺草胺和精草铵膦混用组合混配比1∶2~1∶8较为合适,且以1∶4最佳。

耐草甘膦杂草控制技术研究

柑桔园行间定向喷雾试验结果表明,在41%农达AS中加入70%苯嘧磺草胺WG和助剂Dash不仅能有效控制乌蔹莓、铁苋菜、假一年蓬、加拿大一枝黄花等多种耐草甘膦阔叶杂草的危害,控制多年生杂草的再生,而且作用速度可与20%克无踪AS相当,对柑桔生长安全。从高效、经济、安全的角度综合考虑,三者混用的适宜剂量为41%农达AS 1 000～1 500 g ai/hm^2＋70%苯嘧磺草胺WG 12.5～25.0 g ai/hm^2＋助剂Dash（喷液量的1%）。

苯嘧磺草胺原药高效液相色谱分析方法研究

本文采用高效液相色谱法,以甲醇+磷酸溶液为流动相,使用以ZORBAX Extend-C18、5μm为填料的不锈钢柱和二极管阵列检测器,在270nm波长下对苯嘧磺草胺原药进行分离和定量分析。结果表明,该分析方法的线性相关系数为1.000 0;标准偏差为0.21;变异系数为0.22%;平均回收率为99.4%。

10%苯嘧磺草胺悬浮剂防除冬小麦田阔叶杂草药效及安全性评价

为了验证10%苯嘧磺草胺悬浮剂防除冬小麦(Triticum aestivum L.)田阔叶杂草的田间药效及安全性,采用茎叶喷雾法进行田间药效试验。结果表明,药后20 d,10%苯嘧磺草胺悬浮剂30.0、52.5、75.0、105.0 g/hm2对繁缕[Malachium aquaticum(L.)Moench]、猪殃殃[Galium spurium L.]、婆婆纳[Veronica didyma Tenore]等杂草的综合防效为89.20%~100.00%;药后40 d,株防效为88.60%~100.00%,鲜重防效为89.10%~100.00%。同等用量下该药剂对猪殃殃的防除效果优于婆婆纳和繁缕。田间拟推荐剂量为30.0~75.0 g/hm;。供试药剂在拟推荐剂量内使用可有效防除冬小麦田阔叶杂草,且对冬小麦安全。

新型除草剂苯嘧磺草胺的合成研究

以2-氯-4-氟苯甲酸为起始原料,经硫酸和硝酸硝化,氯化亚砜酰化后与N-甲基-N-异丙基磺酰胺反应得到化合物N-(2-氯-4-氟-5-硝基苯甲酰)-N′-异丙基-N′-甲基磺酰胺;制得N-(2-氯-4-氟-5-硝基苯甲酰)-N′-异丙基-N′-甲基磺酰胺经钯碳加氢硝基还原,然后与氯甲酸乙酯反应得到化合物N-[2-氯-4-氟-5-{(乙氧基羰基)氨基}苯甲酰]-N′-异丙基-N′-甲基磺酰胺;N-[2-氯-4-氟-5-{(乙氧基羰基)氨基}苯甲酰]-N′-异丙基-N′-甲基磺酰胺与3-甲基氨基-4,4,4-三氟丁烯酸乙酯进行环化,得到目的产物苯嘧磺草胺。总收率68.0%(以2-氯-4-氟苯甲酸计)。经核磁谱图分析,所得化合物与目的产物苯嘧磺草胺结构一致。

Control of glyphosate resistant giant ragweed in soybean with preplant herbicides

Giant ragweed was the first glyphosate resistant weed identified in Canada. It is a very competetive weed in row crop production and has been found to drastically reduce yields of soybean;therefore, control of this competitive weed is essential. The objective of this study was to determine effective control options for glyphosate resistant giant ragweed in soybean with herbicides applied preplant. Eighteen herbicide combinations were evaluated in field studies conducted in 2011 and 2012 at five locations with confirmed glyphosate resistant giant ragweed. Glyphosate plus 2,4-D ester or amitrole provided the best control of glyphosate resistant giant ragweed 4 WAA. Glyphosate plus 2,4-D ester provided 98 to 99% control and was equivalent to the weed free check at all locations. Glyphosate plus amitrole provided 90% to 93% control and was equivalent to the weed free check at 4 of 5 locations. Herbicides providing residual activity provided variable control across all locations. Of the herbicides with residual activity evaluated, glyphosate plus linuron provided the best control of glyphosate resistant giant ragweed;however, control was inconsistent across locations and years. Glyphosate plus linuron provided 23% to 99% controland was equal to the weed free check at one location 8 WAA.

Glyphosate-Resistant Canada Fleabane Control with Three-Way Herbicide Tankmixes in Soybean

Eight field trials (2 in 2016, 3 in 2017, 3 in 2018) were conducted in farmers’ fields with heavy infestations of GR Conyza canadensis (Canada fleabane, horseweed or marestail) to evaluate glyphosate (900 g ae ha-1) plus saflufenacil (25 g ai ha-1), 2,4-D ester (500 g ai ha-1) or paraquat (1100 g ai ha-1) applied preplant (PP) as 2-way tankmixes, or in 3-way tankmixes with sulfentrazone (140 g ai ha-1), flumioxazin (107 g ai ha-1) or metribuzin (400 g ai ha-1) for the glyphosate-resistant (GR) C. canadensis control in GR soybean. Glyphosate plus saflufenacil applied PP controlled GR C. canadensis as much as 90%. The addition of sulfentrazone, flumioxazin or metribuzin to the tankmix provided as much as 93%, 96% and 97% control of GR C. canadensis, respectively. Glyphosate plus 2,4-D ester applied PP provided as much as 59% control of GR C. canadensis. The addition of sulfentrazone, flumioxazin or metribuzin to the tankmix provided as much as 60%, 59% and 91% control of GR C. canadensis, respectively. Glyphosate plus paraquat applied PP provided as much as 85% control of GR C. canadensis. The addition of sulfentrazone, flumioxazin or metribuzin to the tankmix provided as much as 88%, 89% and 98% control of GR C. canadensis, respectively. Density and biomass reductions of GR C. canadensis with herbicides evaluated followed the same pattern as weed control evaluations. GR C. canadensis interference reduced soybean yield 66%. Reduced GR C. canadensis interference with the preplant herbicides evaluated provided soybean yield similar to the weed-free control. Results from this study show that glyphosate plus saflufenacil, glyphosate plus 2,4-D ester or glyphosate plus paraquat tankmixed with metribuzin can provide effective control of GR C. canadensis in GR soybean.

Tolerance of Winter Wheat (<i>Triticum aestivum</i>L.) and Under Seeded Red Clover (<i>Trifolium pretense</i>L.) to Fall Applied Post-Emergent Broadleaf Herbicides

The fall application of post-emergent (POST) herbicides on winter wheat provided effective control of emerged winter annual, biennial, and perennial broadleaf weeds. In recent years, wheat producers have seen a shift to these weeds, due in part, to the adoption of reduced-and no-tillage practices and the use of non-residual herbicides such as glyphosate in the preceding soybean and corn crops. The tolerance of winter wheat to ten herbicides, applied POST in the fall, was evaluated between 2008 and 2011 at Exeter and Ridgetown, Ontario. Winter wheat yield was not reduced by applications of MCPA ester, dicamba/ MCPA/ mecoprop, clopyralid, bromoxynil/ MCPA, thifensulfuron /tribenuron +MCPA ester, fluroxypyr +MCPA ester, and pyrasulfotole/ bromoxynil. In contrast, 2,4-D ester and dichlorprop/2,4-D, caused visible injury in June and July of the following year and consistently decreased winter wheat yield by at least 10%. Applications of 100 g a.i. ha-1 saflufenacil also decreased winter wheat yield in two of the four harvest years examined. None of the herbicide options examined were safe on red clover when it was under seeded the spring following winter wheat planting. All herbicides significantly decreased red clover dry biomass one month after wheat harvest.

Control of Glyphosate-Resistant Marestail in Identity-Preserved or Glyphosate-Resistant and Glyphosate/Dicamba-Resistant Soybean with Preplant Herbicides

Two studies, each consisting of six field experiments were conducted in growers’ fields in 2018 and 2019 to determine the optimal herbicide tankmixes, applied preplant (PP) for the control of glyphosate-resistant (GR) marestail in 1) identity-preserved and glyphosate-resistant soybean (Study 1) and, 2) glyphosate/dicamba-resistant soybean (Study 2). There was no significant injury in soybean with the PP herbicides evaluated in both studies. In Study 1, at 8 weeks after treatment (WAA), glyphosate + saflufenacil, glyphosate + 2,4-D ester, glyphosate + pyraflufen/2,4-D, glyphosate +, 4-D choline or glyphosate + halauxifen-methyl, applied PP, controlled GR marestail 93%, 58%, 60%, 67% and 71%, respectively. The addition of metribuzin to the tankmixes of glyphosate + saflufenacil, 2,4-D ester and pyraflufen/2,4-D increased the control to 98%, 91% and 95%, respectively. The addition of metribuzin + chlorimuron-ethyl to 2,4-D choline/glyphosate and glyphosate + halauxifen-methyl increased the control to 94% and 93%, respectively. In Study 2, at 8 WAA, glyphosate/dicamba, applied PP, controlled GR marestail 89% in glyphosate/dicamba-resistant soybean. The addition of metribuzin or saflufenacil to glyphosate/dicamba controlled GR marestail 86% and 97%, respectively. At 8 WAA, S-metolachlor/dicamba controlled GR marestail 83%. The addition of metribuzin or saflufenacil to the above premix controlled GR marestail 87% and 97%, respectively. Density and biomass reductions were similar to visible control. GR marestail interference reduced soybean yield 60% and 53% in Study 1 and 2, respectively. Reduced GR marestail interference with all the herbicide treatments evaluated in both studies resulted in soybean yield that was similar to the weed-free control.

Tolerance of Soybean(Glycine max L.)to Protoporphyrinogen Oxidase Inhibitors and Very Long Chain Fatty Acid Synthesis Inhibitors Applied Preemergence

Nine field experiments were conducted in 2011 and 2012 at various locations in southern Ontario, Canada to determine the tolerance of soybean (Glycine max (L.) Merr.) to herbicides inhibiting protoporphyrinogen oxidase (Protox) and very long chain fatty acid (VLCFA) synthesis applied alone and in combination. Preemergence applications were evaluated for soybean injury, plant height, shoot dry weight, and yield in the absence of weed competition. Early-season soybean injury from the Protox inhibitors persisted 4 weeks after soybean emergence (WAE) with 3%, 5%, and 18% injury for flumioxazin, saflufenacil, and sulfentrazone, respectively. When Protox inhibitors were tank mixed with VLCFA inhibitors (i.e., dimethenamid-P, S-metolachlor, and pyroxasulfone), additive interactions were observed for injury with saflufenacil and sulfentrazone;whereas synergistic interactions were observed with flumioxazin. However, injury subsided over time decreasing from as much as 34% injury 1 WAE for the flumioxazin + S-metolachlor tank mix down to 9% injury 4 WAE. In general, when saflufenacil or flumioxazin were tank mixed with VLCFA inhibitors, greater than expected reductions in height and dry weight were observed indicating synergistic responses;while no interactive effects were detected with sulfentrazone and VLCFA inhibitor tank mixes. For the flumioxazin tank mixes that contained dimethenamid-P or S-metolachlor, the reduction in yield was greater than expected indicating synergistic interactive effects. Yet, all the demonstrated impacts were transient as the yield for soybean treated with any of the Protox inhibitor and VLCFA inhibitor tank mixes tested were similar to the untreated control. Therefore, usage restriction on these mixtures, based on perceived negative yield impact, should be lifted so the herbicides could be combined to expand weed control options.

新型原卟啉原氧化酶抑制剂Y11049的作用特性

为明确新型原卟啉原氧化酶(PPO)抑制剂Y11049[化学名称为2-((6-氟-5-(3-甲基-2,6-二氧代-4-三氟甲基-3,6-二氢嘧啶-1(2H)-基)苯并[d]噻唑-2-基)硫代)丙酸乙酯]的作用特性,本研究以同类型药剂苯嘧磺草胺为对照,选择对Y11049敏感的几种阔叶杂草为测试靶标,采用室内生物测定法,分别研究了环境温度、光照强度、模拟降雨及杂草叶龄对Y11049除草活性的影响,以及Y11049在黄瓜和苘麻植株中的吸收传导特性。结果表明:在有效成分3.75、7.5、15及30 g/hm^(2)剂量下,在15~35℃范围内,Y11049对绿穗苋的除草活性与温度呈显著正相关;强光照(8427 lx)条件下,有效成分60 g/hm^(2)的Y11049对牵牛的鲜重抑制率为95.2%,显著高于中等光照(4200 lx)和低光照(5 lx)条件下的抑制率,说明其为需光型;于施药后4 h模拟降雨,Y11049对苘麻的鲜重抑制率与无降雨处理之间无显著差异;在有效成分30 g/hm^(2)剂量下,Y11049芽前土壤处理对苘麻和反枝苋无活性,对芽后2~8叶期苘麻和反枝苋的鲜重抑制率分别为86.0%~98.6%和86.5%~97.9%,表明其施药适期较长。Y11049可通过根、茎、叶及芽吸收进入植物体内,但传导能力较弱;其作用特性整体与苯嘧磺草胺相近。研究表明,新型PPO抑制剂Y11049在防除非耕地阔叶杂草方面具有较好的应用前景,但以选择温度适宜的晴天施药为宜,且由于其作用方式为触杀,在非耕地应用时需要足够的喷液量以保证均匀喷施于杂草表面。结果可为Y11049的开发应用提供理论依据。

苏门白酒草对草甘膦等除草剂的多抗性检测及防治药剂筛选

苏门白酒草Conyza sumatrensis是中国华南地区常见的阔叶杂草,在果园和非耕地常造成严重危害。本研究采用整株剂量反应法,明确了采自广东省广州市的苏门白酒草疑似抗性种群(GZ-R)对草甘膦、百草枯和敌草快的抗性水平,比对了GZ-R种群和采自广东省清远市的敏感对照种群(QY-S)的草甘膦靶标酶基因EPSPS2片段的差异,并测定了灭草松、氯氟吡氧乙酸等5种茎叶处理剂对不同叶龄苏门白酒草的室内防除效果。结果表明:GZ-R种群对草甘膦和百草枯分别产生了中等水平和高水平抗性,并已对敌草快产生交互抗性,3种药剂对GZ-R种群的LD_(50)值分别是对QY-S种群LD_(50)值的7.2、72.3和6.6倍;与QY-S种群相比,GZ-R种群的EPSPS2基因106位由脯氨酸突变为苏氨酸。在灭草松、氯氟吡氧乙酸或2甲4氯钠推荐剂量下,于4~5叶期施药,苏门白酒草死亡率均为100%,但于6~7叶期和10~12叶期施药,苏门白酒草死亡率显著下降至44.4%~91.7%;而在草铵膦或苯嘧磺草胺推荐剂量下,不同叶龄期施药苏门白酒草的死亡率均为100%,因此在植株生长早期可使用草铵膦和苯嘧磺草胺防除已对草甘膦和百草枯等除草剂产生抗性的苏门白酒草。

液相色谱-串联质谱联用定量分析食品中苯嘧磺草胺残留

基于液相色谱-串联质谱建立了一种食品中苯嘧磺草胺残留定量分析方法。样品经乙腈超声提取、固相萃取柱净化、氮吹浓缩后结合液相色谱-串联质谱实现其定量检测。结果表明:在0.01~10.0 mg/kg范围内苯嘧磺草胺线性关系良好,y=24.136 1x-16.038 5(r=0.999 6),检出限为0.002 mg/kg,定量限为0.006 mg/kg。方法稳定性较好,精密度高,检出限满足GB 2763—2021中苯嘧磺草胺的限值要求,能够为苯嘧磺草胺的监管和监测提供技术支撑。

HPLC法测定32%苯嘧磺草胺·草甘膦可分散油悬浮剂中甲醛的含量

建立一种高效液相色谱方法测定32%苯嘧磺草胺·草甘膦可分散油悬浮剂中甲醛的含量。采用高效液相色谱法,以乙腈+水为流动相,使用以Waters XBridge C_(18)为填料的不锈钢柱和紫外检测器(412 nm),通过测定甲醛与Hantzsch试剂衍生后产生的衍生物,对32%苯嘧磺草胺·草甘膦可分散油悬浮剂中的杂质甲醛进行定量分析。结果表明,甲醛的质量浓度为0.010~1.520 mg/L时(r=0.997)线性关系良好,相对标准偏差为5.9%,平均回收率为105.8%。该分析方法的定量限为0.0030 g/kg,检出限为0.0015 g/kg。该方法回收率良好,测定结果准确可靠,能准确定量分析32%苯嘧磺草胺·草甘膦可分散油悬浮剂中甲醛的含量。

苯嘧磺草胺在高粱上的残留及消解动态

[目的]建立了QuEChERS法结合高效液相色谱-串联质谱(HPLC-MS/MS)测定高粱中苯嘧磺草胺残留的检测方法。[方法]高粱植株和籽粒经乙腈-水提取,土壤经乙腈-0.2%甲酸水提取,经PSA、C_(18)、GCB和无水MgSO_(4)净化,采用HPLC-MS/MS测定,外标法定量。[结果]在0.001~0.5 mg/L范围内,苯嘧磺草胺质量浓度与其响应值线性关系良好。添加的质量分数为0.01、0.1、0.5 mg/kg时,苯嘧磺草胺在高粱植株、土壤和籽粒中的平均回收率在85.6%~101.7%之间,相对标准偏差(RSDs)在1.48%~6.28%之间,定量限(LOQ)均为0.01 mg/kg。结果表明,苯嘧磺草胺在内蒙古和吉林2个试验点土壤中的消解动态符合一级反应动力学方程,半衰期分别为3.5、3.7 d;苯嘧磺草胺在高粱植株、土壤和籽粒基质中的最终残留均低于定量限。[结论]70%苯嘧磺草胺水分散粒剂按照推荐剂量施用收获期安全。试验可以为苯嘧磺草胺的安全使用和最大残留限量(MRL)的制定提供参考依据。

除草剂苯嘧磺草胺的合成进展

苯嘧磺草胺是巴斯夫公司研制并开发的脲嘧啶类除草剂,2009年上市,可防治多种作物田的阔叶杂草,且对作物安全。综述了苯嘧磺草胺及其重要中间体的合成工艺,并简要进行分析与讨论,为该产品的工业化生产提供参考和依据。

新型除草剂苯嘧磺草胺

苯嘧磺草胺是一个新的嘧啶二酮类(脲嘧啶)除草剂,通过抑制原卟啉原氧化酶(PPO),可有效防除绝大数阔叶杂草,包括抗草甘膦和ALS抑制剂的杂草。简要介绍了其化学名称、理化性质、毒性、作用机理、创制经纬、专利情况、合成方法、生物活性及应用等。

苯嘧磺草胺的生物学特性与使用

原卟啉原氧化酶是叶绿素与亚铁原卟啉合成之前四吡咯生物合成途径中最后一种关键酶,此种酶是许多除草剂的作用靶标;原卟啉原氧化酶抑制除草剂施用后导致植物细胞过氧化及光下组织白化。介绍了原卟啉原氧化酶抑制除草剂的一个重要新品种—苯嘧磺草胺的特性及其使用。