11 research outputs found
ORGANOCATALZED SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF LAPACHOL ANALOGUES
Organocatalyzed stereoselective synthesis of lapachol analogues from the Michael addition of naphthaquinone to different α,β-unsaturated ketones is presented. Different secondary and primary amines were tried to synthesise these analogues. A primary amine ((2R)-2-amino-3-phenylpropanoic acid) organocatlyst proved to be an excellent catalyst for asymmetric synthesis of lapacol analogues. Good to high yields and enantioselectivitie were obtained. The synthesized compounds were further screened for antimicrobial activities. The antimicrobial activities were evaluated by Filter paper Disc diffusion Method. The synthesized compounds were screened against different bacteria and fungi. The compound 3b (2-hydroxy-3-[1-(4-nitrophenyl)-3-oxobutyl] naphthalene-1,4-dione dihydrate) showed maximum activity against Pseudomonas Aeruginosa and minimum activity against Eschirichia coli. The rest of the compounds showed moderate antibacterial activities. The same compound also showed maximum antifungal activity against Candidia albicans. Compound 3f (2-hydroxy-3-(4-oxopentan-2-yl) naphthalene-1,4-dione dihydrate) has minimum antifungal activity against Aspergilus flavus. The rest of the compounds were moderately active against the two fungal strains
Bis(sulfonil)etilenos cíclicos como aceptores efectivos en reacciones asimétricas de Michael
[EUS] El trabajo de fin de grado aquí presentado se ha realizado en el departamento de Química
Orgánica I de la Facultad de Química de San Sebastián bajo la supervisión del Dr. Aitor Landa
Álvarez. En este trabajo se estudia el alcance de las reacciones asimétricas de Michael entre las
N1-acil-1H-imidazol-4(5H)-onas y las diferentes vinil bis(sulfonas) promovidas por catalizadores
orgánicos bifuncionales. Hemos observado que las vinil bis(sulfonas) abiertas β-sustituidas no
son eficaces para llevar a cabo las adiciones. Por el contrario, los bis(sulfonil)etilenos cíclicos han
resultado ser unos excelentes aceptores de Michael, proporcionando los correspondientes aductos
con excelentes rendimientos y diastereo- y enantioselectividades[ENG] The end of degree work presented here has been carried out in the Department of Organic
Chemistry I of the Faculty of Chemistry of San Sebastian under the supervision of Dr. Aitor
Landa Álvarez. This work describes some Michael additions between N1-acyl-imidazole-4(5H)-
ones and different vinyl bis(sulfones) promoted by a bifunctional organic catalyst. We have
observed that open β-substituted vinyl bis(sulfones) are not effective Michael acceptors in that
kind of reactions, in contrast to bis(sulfonyl)ethylenes, which have proved to be so effective,
providing excellent yields as well as diastereo- enantioselectivitie
Asymmetric Dual Enamine Catalysis/Hydrogen Bonding Activation
Asymmetric enamine base activation of carbonyl compounds is a well-known and widely used strategy for providing functionalization of organic compounds in an efficient way. The use of solely organic substances, which in most cases are commercially available primary or secondary amines that are easy to obtain, avoids the use of hazardous substances or metal traces, making this type of catalysis a highly convenient methodology from a sustainable point of view. In many cases, the reactivity or the stereoselectivity obtained is far from being a practical and advantageous strategy; this can be improved by using a hydrogen bonding co-catalyst that can help during the activation of one species or by using a bifunctional catalyst that can direct the approximation of reagents during the reaction outcome. In this review, we describe the most efficient methodologies that make use of a dual activation of reagents for performing α-functionalization (enamine activation) or remote functionalization (such as dienamine or trienamine activation) of carbonyl compounds.PID2020-118422GB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future” are gratefully acknowledged together with the Basque Government (Grupos IT1558-22) and the University of the Basque Country (UPV/EHU)
Development of controlled drug delivery systems using uniform nanoporous materials as matrices
Ph.DDOCTOR OF PHILOSOPH
Carbon-11 Labeled Amino Acids and Peptides: Chemistry and Applications
Windhorst, A.D. [Promotor]Poot, A.J. [Copromotor
Enantioselective Construction of Tetrasubstituted Carbon Stereocenters via Chiral Phosphoric Acid-Catalyzed Friedel–Craft Alkylation of Indoles with 5-Substituted Hydroxybutyrolactams
The first intermolecular organocatalytic enantioselective addition of indoles to prochiral 5-membered cyclic N-acyliminium ions, generated from 5-hydroxy-,-unsaturated pyrrolidin-2-ones is reported hereinafter. The reaction proceeds smoothly with a range of 5-hydroxy-5-substituted-,-unsaturated pyrrolidin-2-ones and indoles using BINOL-derived phosphoric acid catalyst to afford ,-unsaturated lactams embedding a tetrasubstituted stereogenic center in high yields and enantioselectivitie
A convenient route to enantiomerically enriched furo-fused BINOL derivative
940-943A simple
synthetic route has been developed to obtain a new axially chiral, C2-symmetric, modified BINOL with the
introduction of methyl substituted furan ring fused to the BINOL 1
framework. The successful placement of the furan moiety at C-7; C-8 and
C-7′; C-8′ positions of 1 resulted in the sterically demanding BINOL
derivative. The synthesis of
both enantiomers of methyl-substituted furo-fused BINOL has been carried out
with high enantioselectivitie
Strategy of total synthesis based on the use of Rh-catalyzed stereoselective 1,4-addition
International audienceIn 1998, Hayashi and Miyaura reported the first asymmetric conjugate addition of aryl- and alkenyl-boronic acids to α,β-unsaturated ketones using chiral rhodium complexes as catalysts. During the last decade, this reaction has been developed quickly and the enantioselectivity was significantly improved with the emergence of new phosphine ligands. In addition to the methodological work, this reaction was applied as a key step in the total synthesis of natural compounds. The purpose of this paper focuses on examples of the use of this reaction to prepare elaborated chiral molecules with high diastereoselectivies and/or enantioselectivitie