1965-41-9Relevant academic research and scientific papers
Complementary performance of organoselenides and organotellurides as antimicrobials agents
Borges, Felipe G.,Zugman, Tay,Bandeira, Pamela T.,Dalmolin, Mara C.,Scariot, Débora B.,Garcia, Francielle P.,de Oliveira, Alfredo R.M.,Nakamura, Celso V.,Piovan, Leandro
, p. 462 - 475 (2021/02/12)
Fungi and bacteria are well-known pathogens for plants, fruits, and animals, including humans. In this context, the prospection of antimicrobial agents is crucial to provide new alternatives for the treatment of microbial diseases. Hence, selenium- and tellurium-containing compounds are underexploited and herein, antimicrobial activity of several organochalcogenated compounds was evaluated against Gram-negative and Gram-positive bacteria and fungi. A direct comparison between Se- and Te-containing compounds was performed, as well as structure-activity relationship studies. Among assayed compounds, secondary Se-amines LQ16 and LQ20 and secondary Te-amine LQ28 showed excellent results against a variety of fungi, while primary Te-amine LQ10 demonstrated promising results against bacteria. These results suggest organoselenides and organotellurides may be used for the development of new antimicrobial agents.
Synthesis, Antioxidant Activity and Cytotoxicity of N-Functionalized Organotellurides
Bandeira, Pamela T.,Dalmolin, Mara C.,de Oliveira, Mariana M.,Nunes, Karine C.,Garcia, Francielle P.,Nakamura, Celso V.,de Oliveira, Alfredo R.M.,Piovan, Leandro
, p. 410 - 415 (2019/01/04)
The use of antioxidants is the most effective means to protect the organism against cellular damage caused by oxidative stress. In this context, organotellurides have been described as promising antioxidant agents for decades. Herein, a series of N-functionalized organotellurium compounds has been tested as antioxidant and presented remarkable activities by three different in vitro chemical assays. They were able to reduce DPPH[rad] radical with IC50 values ranging from 5.08 to 19.20 μg mL?1, and some of them also reduced ABTS[rad]+ radical and TPTZ-Fe3+ complex in ABTS[rad]+ and FRAP assays, respectively. Initial structure-activity relationship discloses that the nature of N-substituent strongly influenced both activity and cytotoxicity of the studied compounds. Furthermore, radical scavenging activities of N-functionalized organotellurides have been compared with those of their selenilated congeners, demonstrating that the presence of tellurium atom has an essential role in antioxidant activity.
Straightforward microwave-assisted synthesis of organochalcogen amines by reductive amination
Dalmolin, Mara C.,Bandeira, Pamela T.,Ferri, Matheus S.,de Oliveira, Alfredo R.M.,Piovan, Leandro
supporting information, p. 32 - 39 (2018/08/28)
Organoselenium and organotellurium amines have been shown to present a broad range of interesting properties for both synthetic and biological applications. Despite the current interest in this class of compounds, only few methods to access organochalcogen amines are described in literature, most which involve restrictive conditions associated with displacement reaction, metal-assisted reactions or enzymatic approach. In general, these methods produce organochalcogen amines in poor yields, by long reactions that require protective groups. In this regard, a set of aryl chalcogen (Se, Te) amines were prepared by reductive amination employing a microwave-assisted one-pot protocol. This approach offered a convenient and versatile method to synthesize primary and secondary organochalcogen amines with significantly short time reactions (5–10 min) and satisfactory yields (40–89%).
ω-Transaminases as efficient biocatalysts to obtain novel chiral selenium-amine ligands for Pd-catalysis
Andrade, Leandro H.,Silva, Alexandre V.,Milani, Priscila,Koszelewski, Dominik,Kroutil, Wolfgang
experimental part, p. 2043 - 2051 (2010/07/03)
ω-Transaminases have been evaluated as biocatalysts in the reductive amination of organoselenium acetophenones to the corresponding amines, and in the kinetic resolution of racemic organoselenium amines. Kinetic resolution proved to be more efficient than the asymmetric reductive amination. By using these methodologies we were able to obtain both amine enantiomers in high enantiomeric excess (up to 99%). Derivatives of the obtained optically pure o-selenium 1-phenylethyl amine were evaluated as ligands in the palladium-catalyzed asymmetric alkylation, giving the alkylated product in up to 99% ee.
First dynamic kinetic resolution of selenium-containing chiral amines catalyzed by palladium (Pd/BaSO4) and Candida antartica lipase (CAL-B)
Andrade, Leandro H.,Silva, Alexandre V.,Pedrozo, Eliane C.
scheme or table, p. 4331 - 4334 (2009/10/26)
An efficient method for chemoenzymatic dynamic kinetic resolution of selenium-containing chiral amines (organoselenium-1-phenylethanamines) has been developed, leading to the corresponding amides in excellent enantioselectivities and high isolated yields.
