Southern corn leaf blight (SCLB), caused by Bipolarismaydis, is one of the most devastatingdiseases affecting maize production. However,only one SLCB resistance gene, conferring partialresistance, is currently known, ...Southern corn leaf blight (SCLB), caused by Bipolarismaydis, is one of the most devastatingdiseases affecting maize production. However,only one SLCB resistance gene, conferring partialresistance, is currently known, underscoring theimportance of isolating new SCLB resistancerelatedgenes. Here, we performed a comparativeproteomic analysis and identified 258 proteinsshowing differential abundance during the maizeresponse to B. maydis. These proteins included anascorbate peroxidase (Zea mays ascorbate peroxidase1 (ZmAPX1)) encoded by a gene locatedwithin the mapping interval of a previously identifiedquantitative trait locus associated with SCLBresistance. ZmAPX1 overexpression resulted inlower H_(2)O_(2) accumulation and enhanced resistanceagainst B. maydis. Jasmonic acid (JA)contents and transcript levels for JA biosynthesisand responsive genes increased in ZmAPX1-overexpressing plants infected with B. maydis,whereas Zmapx1 mutants showed the oppositeeffects. We further determined that low levels of H_(2)O_(2) are accompanied by an accumulation of JAthat enhances SCLB resistance. These resultsdemonstrate that ZmAPX1 positively regulatesSCLB resistance by decreasing H_(2)O_(2) accumulationand activating the JA-mediated defensesignaling pathway. This study identified ZmAPX1as a potentially useful gene for increasing SCLBresistance. Furthermore, the generated datamay be relevant for clarifying the functions ofplant APXs.展开更多
Two new Cl-symmetric primary-secondary diamines were synthesized via the reaction of （S,S）-1,2- diphenyl ethylene diamine with 3,5-ditert-butyl salicylal- dehyde and salicylaldehyde, respectively, followed by reduct...Two new Cl-symmetric primary-secondary diamines were synthesized via the reaction of （S,S）-1,2- diphenyl ethylene diamine with 3,5-ditert-butyl salicylal- dehyde and salicylaldehyde, respectively, followed by reduction with NaBH4. The combination of the ligand from 3,5-ditert-butyl salicylaldehyde with CuBr could effciently catalyze the Henry reaction to afford β- nitroalkanols in moderate to good yields （up to 87%） and high enantioselectivities （up to 88% ee）. A possible mechanism of the reaction was proposed.展开更多
Phthalimide derivatives as nitrogen nucleophiles with α,β-unsaturated aldehydes for asymmetric aza-Michael additions have been reported. The reactions proceed smoothly to afford corresponding Michael adducts in goo...Phthalimide derivatives as nitrogen nucleophiles with α,β-unsaturated aldehydes for asymmetric aza-Michael additions have been reported. The reactions proceed smoothly to afford corresponding Michael adducts in good yields （up to 98%） and enantioselectivities （up to 95% ee）.展开更多
基金supported by the National Natural Science Foundation of China (31872872 and U1804113)the National Key Research and Development Program of China (2016YFD0101003)
文摘Southern corn leaf blight (SCLB), caused by Bipolarismaydis, is one of the most devastatingdiseases affecting maize production. However,only one SLCB resistance gene, conferring partialresistance, is currently known, underscoring theimportance of isolating new SCLB resistancerelatedgenes. Here, we performed a comparativeproteomic analysis and identified 258 proteinsshowing differential abundance during the maizeresponse to B. maydis. These proteins included anascorbate peroxidase (Zea mays ascorbate peroxidase1 (ZmAPX1)) encoded by a gene locatedwithin the mapping interval of a previously identifiedquantitative trait locus associated with SCLBresistance. ZmAPX1 overexpression resulted inlower H_(2)O_(2) accumulation and enhanced resistanceagainst B. maydis. Jasmonic acid (JA)contents and transcript levels for JA biosynthesisand responsive genes increased in ZmAPX1-overexpressing plants infected with B. maydis,whereas Zmapx1 mutants showed the oppositeeffects. We further determined that low levels of H_(2)O_(2) are accompanied by an accumulation of JAthat enhances SCLB resistance. These resultsdemonstrate that ZmAPX1 positively regulatesSCLB resistance by decreasing H_(2)O_(2) accumulationand activating the JA-mediated defensesignaling pathway. This study identified ZmAPX1as a potentially useful gene for increasing SCLBresistance. Furthermore, the generated datamay be relevant for clarifying the functions ofplant APXs.
文摘Two new Cl-symmetric primary-secondary diamines were synthesized via the reaction of （S,S）-1,2- diphenyl ethylene diamine with 3,5-ditert-butyl salicylal- dehyde and salicylaldehyde, respectively, followed by reduction with NaBH4. The combination of the ligand from 3,5-ditert-butyl salicylaldehyde with CuBr could effciently catalyze the Henry reaction to afford β- nitroalkanols in moderate to good yields （up to 87%） and high enantioselectivities （up to 88% ee）. A possible mechanism of the reaction was proposed.
文摘Phthalimide derivatives as nitrogen nucleophiles with α,β-unsaturated aldehydes for asymmetric aza-Michael additions have been reported. The reactions proceed smoothly to afford corresponding Michael adducts in good yields （up to 98%） and enantioselectivities （up to 95% ee）.
