In the last few decades transition metal-catalyzed direct C-H bond functionalization has served as a valuable tool for the construction of complex molecules from more simple starting materials, mainly due to its atom- and step-economical nature. Nowadays, the field of third row transition metal catalyzed C-H functionalization is being extensively studied as a cheaper and attractive alternative...
The ease of the unsaturated system reactivity proceeding via -silyl carbocation ion can be explained by the stabilizing effects of the silicon-carbon bond interaction with carbocation ion - known as -silicon effect. This can be achieved by either vertical (hyperconjugation) or non-vertical (formation of cyclic silonium ion) stabilization. The formation of the latter, in combination with...
Heterocycles with an azido-azomethine structural entity are interesting due to their intrinsic dynamic azide-tetrazole tautomeric equilibrium in the solution phase [1] alongside rich azide functional group chemistry [2].
Herein, a method for the synthesis of 5-substituted tetrazolo[1,5-a]pyrido[2,3 e] pyrimidines from 2,4-diazidopyrido[3,2-d]pyrimidine in SNAr reactions with N-, O-, and S ...
Synthesis of fluorine containing molecules is of great interest due to its unique properties and vast application in pharmaceuticals, agrochemicals and materials [1].
Previously in our group we have developed fluoromethylene transfer from fluromethylsulfonium salts [2, 3]. Herein we wish to report preliminary results on synthesis of reagents 1 and its initial application in carbene transfer...
C-H activation of betulin, oleanolic acid and ursolic acid
Target purine compound 2 was designed with an aim to be used as a potential system for photo-catalysis. For the synthesis of 2, derivatization of C(6), C(8) and N(9) positions of 6-chloropurine (1) with A, B and C moieties is required. Several synthetic pathways were designed and have been tested. In the end, target compound 2 was obtained, using the...
β-Caryophyllene is one of the most abundant sesquiterpenes found in nature, therefore it is available at low price from several commercial sources. The unusual structure of β-caryophyllene with two stereodefined chiral centers renders this terpene an attractive renewable starting material for the access of diverse high value compounds.
We demonstrate that β-caryophyllene and its oxide can be...
In the last couple of decades, high-valent cobalt catalysis has been used as a valuable tool for C-H bond activation and functionalization.1 The use of cobalt(II) salt catalysts in combination with bidentate directing groups has proven to be an effective strategy for various C-H bond transformations.2,3 With cobalt being less expensive alternative to noble metals, it also displays unique...
Quinazolines and indazoles can be synthesized starting from 2-formylphenylboronic acids using copper-promoted C-N bond formation with subsequent heterocyclization.
Carbonic anhydrases (CA, EC 4.2.1.1) are essential metalloenzymes found across all kingdoms of life. These enzymes are involved in many important physiological processes, as they catalyse the reversible hydration of carbon dioxide [1]. To date, 15 different human CA isoforms have been identified, out of which CA IX and XII isoforms are highly overexpressed in different tumour types and may...
SYNTHESIS AND USE OF NOVEL MOLECULARLY IMPRINTED POLYMERS FOR SELECTIVE EXTRACTION OF CATECHOLAMINES AND THEIR METABOLITES
JAUNU MOLEKULĀRI IMPRINTĒTU POLIMĒRU SINTĒZE UN TO PIELIETOŠANA SELEKTĪVAI KATEHOLAMĪNU UN TO METABOLĪTU CIETFĀZES EKSTRAKCIJAI
Artūrs Šilaks, Antons Podjava
Laboratory of Chromatography and Mass Spectrometry, Department of Chemistry, Academic Center of Natural...