Iminophosphorane-mediated efficient synthesis of new tricyclic 3,5-dihydro-1,2,3-triazolo[4,5-d]-1,2,4-triazolo[1,5-a]pyrimidin-9-ones

Therapeutic potential of flavonoids in spinal cord injury

Spinal cord injury (SCI) is a catastrophic event that can profoundly affect a patient's life, with far-reaching social and economic effects. A consequential sequence of SCI is the significant neurological or psychological deficit, which obviously contributes to the overall burden of this condition. To date, there is no effective treatment for SCI. Therefore, developing novel therapeutic strategies for SCI is highly prioritized. Flavonoids, one of the most numerous and ubiquitous groups of plant metabolites, are the active ingredients of traditional Chinese medicine such as Scutellaria baicalensis Georgi (Huang Qin) or Ginkgo biloba (Ying Xin). Accumulated research data show that flavonoids possess a range of key pharmacological properties such as anti-inflammatory, anti-oxidant, anti-tumor, anti-viral, anti-cardiovascular disease, immunomodulatory, and neuroprotective effects. Based on this, the flavonoids show therapeutic potential for SCI diseases. In this paper, we will review the pharmacological properties of different types of flavonoids for the treatment of SCI diseases, and potential underlying biochemical mechanisms of action will also be described.

Recent development of synthetic preparation methods for guanidines via transition metal catalysis

This article provides an overview of guanidine synthesis via transition-metal-catalyzed reactions including cycloaddition, guanylation and tandem guanylation/cyclization.

Synthesis and structures of substituted triphenyl(phenylimino)phosphoranes

Three substituted triphenyl(phenylimino)phosphoranes, namely (4-cyanophenylimino)triphenylphosphorane, C(25)H(19)N(2)P, (I), (4-nitrophenylimino)triphenylphosphorane, C(24)H(19)N(2)O(2)P, (II), and (3-nitrophenylimino)triphenylphosphorane, C(24)H(19)N(2)O(2)P, (III), were synthesized as precursors for the preparation of substituted diphenylcarbodiimides. All three compounds display a supramolecular arrangement in which the substituted benzene rings are organized in an antiparallel fashion. The nitro group on the ring participates in C-H...O and O...pi interactions, forming intermolecular dimers. Compound (III) shows disorder which involves the rotation of one of the phenyl rings of the triphenylphosphine group.

A facile synthesis and fungicidal activities of 2-(alkylamino)-5,6-dimethylthieno[2,3-d]pyrimidin-4(3H)-ones

The aza-Wittig reactions of iminophosphorane 3 with aromatic isocyanates generated carbodiimides 4, which were reacted with alkylamines under mild conditions to give a series of 2-(alkylamino)-5,6-dimethylthieno[2,3-d]pyrimidin-4(3H)-ones 6 and 8 in satisfactory yield. Their structures were confirmed by ¹H NMR, EI-MS, IR and elementary analysis, and compound 8c was further analyzed by single-crystal X-ray diffraction. The preliminary bioassays indicated that these compounds showed excellent fungicidal activities against six kinds of fungi.

Synthesis and herbicidal activity of novel pyrazolo[3,4-d]pyrimidin-4-one derivatives containing aryloxyphenoxypropionate moieties

The 6-(4-alkoxycarbonylalkoxy)phenoxy-3-alkylthio(alkylsulfonyl)-1-phenyl-5-(substituted phenyl)pyrazolo[3,4-d]pyrimidin-4-ones 6 and 7 have been synthesized via the tandem aza-Wittig and annulation reactions of the corresponding iminophosphoranes 4, aromatic isocyanates, and substituted phenols 2 in 52-98% yields. Their structures were clearly verified by spectroscopic data (IR, (1)H NMR, (13)C NMR, MS, and elemental analysis or X-ray diffraction crystallography). And the results of preliminary bioassay indicated that these title compounds possess potential herbicidal activity against the root of rape and barnyard grass.