Asymmetric Construction of Bispiro-Cyclopropane-Pyrazolones via a [2+1] Cyclization Reaction by Dipeptide-Based Phosphonium Salt Catalysis
We reported herein an efficient alternative for asymmetric synthesis of structurally complicated chiral bispiro-cyclopropane-pyrazolones via dipeptide-based phosphonium salt catalyzed [2+1] cyclization of 2,3-dioxopyrrolidines and halogenated pyrazolones. With this catalytic asymmetric protocol, a broad range of bispiro heterocyclic compounds bearing a pyrazolone unit were prepared in high yields with excellent diastereo- and enatioselectivities. Of note, this transformation proceeds in a really short time under mild reaction conditions. (Figure presented.).
Cascade assembling of pyrazolin-5-ones and benzylidenemalononitriles: The facile and efficient approach to medicinally relevant spirocyclopropylpyrazolone scaffold
A new cascade reaction provides a direct transformation of pyrazolin-5-ones and benzylidene-malononitriles by the action of bromine into substituted spirocyclopropylpyrazolones in 60-88% yields. This process can be realized in two variants, namely, (1) by treatment with bromine in the presence of base and (2) by treatment with bromine only with heating. These facile and efficient one-step cascade processes lead to the spirocyclopropylpyrazolone framework, which is present in a perspective class of compounds with prominent pharmacological and physiological activity.
Vereshchagin, Anatoly N.,Elinson, Michail N.,Korshunov, Aleksander D.,Korolev, Victor A.,Egorov, Mikhail P.
With herbicidal active pyrazole ether compounds and the use thereof
The invention relates to the technical field of herbicides, and particularly discloses a pyrazole ether compound with herbicidal activity and application thereof. The pyrazole ether compound with the herbicidal activity is a general-formula compound, and the specification specifically discloses 12 kinds of compounds. An experiment result shows that the general-formula compound has high biological activity on weeds and it is hopeful that the pyrazole ether compound serves as herbicide in agriculture and other fields.
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(2018/10/19)
Synthesis new and novel aryl thiazole derivatives compounds
Six new compounds of Thiazoles family was synthesis from condensation reaction of some compounds from pyrazolines. NMR, IR and elemental analysis was used for identification of these compounds. Position of aliphatic and aromatic hydrogens in pyrazolone and thiazole cycles had established proceeding of identification. Most of obtained compounds like aciform crystals, their color is white and yellow. Reaction time and yield of these compounds had shown better results as compared with other thiazole derivations.