516-05-2Relevant articles and documents
An Additional Negative Feedback Loop in the Classical Belousov-Zhabotinsky Reaction: Malonyl Radical as a Second Control Intermediate
Foersterling, Horst-Dieter,Noszticzius, Zoltan
, p. 2740 - 2748 (1989)
Reactions of malonyl radicals with inorganic bromine species (oxidation numbers -1 to +5) of the Belousov-Zhabotinsky (BZ) reaction are investigated in 1 M sulfuric acid medium by electron spin resonance spectroscopy in continuous-flow experiments.A very high reaction rate is found for BrO2. (k7 ca. 5*1E9 M-1 s-1), followed by Br2 and HOBr (k9 -1 s-1 and k8 -1 s-1, respectively).At high concentrations acidic bromate and bromide have some effect too, but this is probably due to indirect reactions.The results indicate that malonyl radical plays an important role as a second control intermediate besides bromide ion in the oscillatory mechanism of the BZ reaction.
Biosynthesis of epothilone intermediates with alternate starter units: Engineering polyketide-nonribosomal interfaces
O'Connor, Sarah E.,Walsh, Christopher T.,Liu, Fei
, p. 3917 - 3921 (2003)
The early steps of epothilone biosynthesis were reprogrammed in vitro by incorporating enzyme subunits (e.g. EntB, EntE) from other biosynthetic pathways into the epothilone (Epo) assembly line (see scheme). Recognition sequences identified at the C termini of the epothilone biosynthetic proteins enabled heterologous enzyme transfer when fused to noncognate proteins, as a step toward the reengineering of biosythetic pathways to produce natural product analogues in vivo.
Novel weeding preparation and preparation method thereof
-
Paragraph 0047-0048, (2021/06/22)
The invention relates to the technical field of herbicides, in particular to a novel weeding preparation and a preparation method thereof. The novel weeding preparation includes at least one compound of formula (1) or formula (2). The novel weeding preparation is prepared by combining two compounds with novel structures, and parasitic weeds can be prevented and removed by adopting a 'suicide' germination strategy by utilizing the characteristic that parasitic weed seeds can germinate only by being stimulated and induced by allelochemicals, that is, before crops are planted, proper allelochemicals are sprayed on the land to induce the weed seeds to germinate, then the weeds finally die due to the fact that no corresponding hosts provide water and nutrition, and the purpose of effectively killing parasitic weed seed banks can be achieved. By using the weeding preparation provided by the invention, the soil inventory of weed seeds can be reduced, prevention and removal can be carried out before seedling emergence, the problems of crop quality reduction, pesticide residues, environmental pollution and the like are avoided, and the weeding preparation is a sustainable ecological parasitic weed comprehensive prevention and control strategy.
Compounds prepared based on cinnamic acid compounds and capable of promoting germination of parasitic plant seeds and preparation method of compounds prepared based on cinnamic acid compounds
-
Paragraph 0025, (2021/06/22)
The invention discloses compounds prepared on the basis of cinnamic acid compounds and capable of promoting seed germination of parasitic plants and a preparation method of the compounds prepared based on the cinnamic acid compounds, and particularly relates to the technical field of seed germination. The structural general formula of the compounds prepared based on the cinnamic acid compounds is shown in a formula (1), wherein the group R is any one selected from the group consisting of 2-CH3, 3-CH3, 4-CH3, 2,3-CH3, 2,4-CH3, 3,5-CH3, 2-C2H5, 3-C2H5, 4-C2H5, 4-C(CH3)3, 2-OCH3, 3-OCH3, 4-OCH3, 3,4-OCH3, 3,5-OCH3, 2-OC2H5, 3-OC2H5, 4-OC3H7, 2-F, 3-F, 4-F, 2-Cl, 3-Cl, 4-Cl, 2-Br, 3-Br, 4-Br, 2-OCF3-6-Br, 3-OH, 2,3,4-OH, 2-F-3-OCH3, 3-OCH2Ph, 2,5-F, 3-CN, 2-OCH3-5-F, 3,4,5-F, 4-F-3-Cl, 2-CH3-3-F, 2-F-3-Br, 2,5-F, 2,4-F, 3,4-F, 4-OH-3-CH3, 3-CH3-5-CF3, 2,3,4-OCH3, 4-CF3, 4-F-3-Br, 3,5-CF3, 3,4-Cl, 3,4-F, 4,5-OCH3-2-Br and 4-OCH3-3-Br. The compound provided by the invention has the advantage of being capable of promoting seed germination of parasitic plants.
Compound capable of bidirectionally regulating plant growth and preparation method thereof
-
Paragraph 0057-0064, (2021/06/22)
The invention discloses a compound capable of bidirectionally regulating plant growth and a preparation method thereof, and particularly relates to the technical field of plant growth, and the structural general formula of the compound is as shown in formula (1). The compound provided by the invention is novel in structure, is not recorded in the prior art, can be used for preparing growth regulators for regulating the growth of main roots and lateral roots of plants under different concentration conditions, and can inhibit the growth of the main roots and promote the growth of fibrous roots in micromole. In nanomole, growth of fibrous roots is only promoted, and main roots are not affected. Targeted regulation and control can be carried out according to the growth requirements of different plants.
Compound prepared based on indole-3-carboxylic acid and capable of promoting germination of parasitic plant seeds, and preparation method thereof
-
Paragraph 0026, (2021/07/08)
The invention discloses a compound prepared based on indole-3-carboxylic acid and capable of promoting seed germination of parasitic plants, and a preparation method thereof and particularly relates to the technical field of seed germination. The structural general formula of the compound is shown in the formula (1) in the specification. In the formula, the group R is selected from at least one of 4-CH3, 5-CH3, 6-CH3, 7-CH3, 4-F, 5-F, 6-F, 7-F, 4-Cl, 5-Cl, 6-Cl, 7-Cl, 4-Br, 5-Br, 6-Br, 7-Br, 5-NO2, 4-OCH3, 5-OCH3, 5-OH, 5, 6-2F, 5-OCH2Ph, 4, 7-2Cl, 4-C2H5 and 4-OC2H5; and n is equal to 1 or 2 or 3. The compound provided by the invention has the advantage of being capable of promoting germination of striga asiatica seeds.
Preparation of mono-substituted malonic acid half oxyesters (SMAHOs)
Condon, Sylvie,Le Gall, Erwan,Pichon, Christophe,Presset, Marc,Xavier, Tania
supporting information, p. 2085 - 2094 (2021/09/02)
The use of mono-substituted malonic acid half oxyesters (SMAHOs) has been hampered by the sporadic references describing their preparation. An evaluation of different approaches has been achieved, allowing to define the best strategies to introduce diversity on both the malonic position and the ester function. A classical alkylation step of a malonate by an alkyl halide followed by a monosaponification gave access to reagents bearing different substituents at the malonic position, including functionalized derivatives. On the other hand, the development of a monoesterification step of a substituted malonic acid derivative proved to be the best entry for diversity at the ester function, rather than the use of an intermediate Meldrum acid. Both these transformations are characterized by their simplicity and efficiency, allowing a straightforward access to SMAHOs from cheap starting materials.
Macrolactam Synthesis via Ring-Closing Alkene-Alkene Cross-Coupling Reactions
Goh, Jeffrey,Loh, Teck-Peng,Maraswami, Manikantha
supporting information, p. 9724 - 9728 (2020/12/21)
Reported herein is a practical method for macrolactam synthesis via a Rh(III)-catalyzed ring closing alkene-alkene cross-coupling reaction. The reaction proceeded via a Rh-catalyzed alkenyl sp2 C-H activation process, which allows access to macrocyclic molecules of different ring sizes. Macrolactams containing a conjugated diene framework could be easily prepared in high chemoselectivities and Z,E stereoselectivities.
Exploring the Promiscuous Enzymatic Activation of Unnatural Polyketide Extender Units in Vitro and in Vivo for Monensin Biosynthesis
Grote, Marius,Schulz, Frank
, p. 1183 - 1189 (2019/03/11)
The incorporation of new-to-nature extender units into polyketide synthesis is an important source for diversity yet is restricted by limited availability of suitably activated building blocks in vivo. We here describe a straightforward workflow for the biogenic activation of commercially available new-to-nature extender units. Firstly, the substrate scope of a highly flexible malonyl co-enzyme A synthetase from Streptomyces cinnamonensis was characterized. The results were matched by in vivo experiments in which the said extender units were accepted by both the polyketide synthase and the accessory enzymes of the monensin biosynthetic pathway. The experiments gave rise to a series of predictable monensin derivatives by the exploitation of the innate substrate promiscuity of an acyltransferase and downstream enzyme functions.
Photodegradation of Myrigalone A, an Allelochemical from Myrica gale: Photoproducts and Effect of Terpenes
Khaled, Amina,Sleiman, Mohamad,Darras, Etienne,Trivella, Aurélien,Bertrand, Cédric,Inguimbert, Nicolas,Goupil, Pascale,Richard, Claire
, p. 7258 - 7265 (2019/07/08)
This study investigated the environmental fate of myrigalone A, a light absorbing natural herbicide found on leaves and fruits of Myrica gale. Myrigalone A was irradiated in water and as a dry solid deposit to simulate reactions on leaves, alone and in the presence of the terpenes generated by Myrica gale. The phototransformation was fast (t1/2 = 35 min in water). Analyses by liquid chromatography coupled to high resolution orbitrap electrospray mass spectrometry (MS) and gas chromatography-MS revealed the formation of 11 photoproducts in water and solid and 9 in gaseous phase. Some were detected in the leaf glands and oil covering the fruits of Myrica gale, which suggested that photodegradation occurred in the field. Moreover, myrigalone A photoinduced the oxidation of terpenes that in turn protected it against photolysis. This highlights the need for additional research on the effect of terpenes on the photodegradation of pesticides on vegetation.
