17 research outputs found
Synthesis of new organocatalysts having ortho-anilinyl-ethanol structure
No full textSynthesis of new organocatalysts having ortho-anilinyl-ethanol structure
Paolo Lupattelli,* Nadia Di Blasio, Lucia Chiummiento, Maria Funicello
Department of Chemistry “Antonio Mario Tamburro”, University of Basilicata,
v.le Ateneo Lucano 10, 85100 Potenza (Italy). email: [email protected]
Increasing numbers of industrial applications are now based on asymmetric organocatalytic reactions, and the "green" aspect of this chemistry coupled with the catalysts’ sustainability, is widely considered for replacing reactions based on metal catalysis.1 Among the various activation methods, aminocatalysis relates to the particular reactivity of the nitrogen.
For many years our research group has been concerned with the synthesis of 2,3-diaryloxiranes and their elaboration via regio- and stereoselective ring opening reactions, with the aim to afford, in a simple and immediate way, functionalized 1,2-diarylethanols.2 Recently a general regioselective reductive ring opening reaction was optimized and different enantiopure ortho-anilinyl-phenylethanols were prepared.3
By the use of suitable oxo-nucleophiles and acid catalysts, diastereoisomeric anilinyldiols were also obtained alternatively, in enantiospecific manner. Enantiopure aminoethers 1-2, and aminodiethers 3-4 were prepared starting from enantiopure trans epoxide 5 which were transformed into aminoalcohols 6, aminodiol 7 and dioxolane 8 by original procedure of regio- and stereoselective ring opening reactions. By selective alkylations of anilinyl alcohols recently optimized by our research group, compounds 7 and 8 were easily transformed into final products 1-3 with different substituents R1 and R2. Analogously, dioxolane 8 was elaborated using classical transacetalization reactions and reductions furnishing 4. Results of their efficiency in terms of acceleration and asymmetric induction in enantioselective organocatalytic reactions (aldol reactions, Michael additions, -heteroatom functionalizations of carbonyl) will also be presented.
1) (a) Dalko, P.I. Enantioselective Organocatalysis Wiley-VCH, 2007. (b) Blaser, H.U.; Pugin, B.; Spindler, F. J. Mol. Catal., Chemical 2005, 231, 1-20. (c) Thirsk, C.; Jay, D. Chem. Ind. 2004, 16, 15-17.
2) (a) Bonini, C.; Lupattelli, P. ARKIVOC, 2008, (viii), 150-182. (b) Solladié-Cavallo, A.; Lupattelli, P.; Bonini, C.; Ostuni, V.; Di Blasio, N. J. Org. Chem. 2006, 71, 9891. (c) Solladié-Cavallo, A.; Lupattelli, P.; Bonini, C. J. Org. Chem. 2005, 70, 1605.
3) Di Blasio, N.; Lopardo, M.T.; Lupattelli, P. Eur. J. Org. Chem. 2009, 938-944
Synthesis of New Thienyl Ring Containing HIV-1 Protease Inhibitors: Promising PreliminaryPharmacological Evaluation against Recombinant HIV-1 Proteases
No full textAseries of new thienyl ring containing analogues of nelfinavir and saquinavir with different substitution patterns were synthesized from suitable enantiopure diols. Their inhibitory activity against wild type recombinant HIV-1 protease was evaluated. In general thienyl groups spaced from the core by a methylene group gave products showing IC50 in the nanomolar range, irrespective of the type and the substitution pattern of the heterocycle. The range of activity of the two most active compounds is substantially maintained or even increased against two commonly selected mutants, under drug pressure, such as V32I and V82A
Synthesis and biological evaluation of new simple indolic non peptidic HIV Protease inhibitors: The effect of different substitution patterns
No full textNew structurally simple indolic non peptidic HIV Protease inhibitors were synthesized from (S)-glycidol
by regioselective methods. Following the concept of targeting the protein backbone, different substitution
patterns were introduced onto the common stereodefined isopropanolamine core modifying the type
of functional group on the indole, the position of the functional group on the indole and the type of the
nitrogen containing group (sulfonamides or perhydroisoquinoline), alternatively. The systematic study
on in vitro inhibition activity of such compounds confirmed the general beneficial effect of the 5-indolyl
substituents in presence of arylsulfonamide moieties, which furnished activities in the micromolar range.
Preliminary docking analysis allowed to identify several key features of the binding mode of such compounds
to the protease
1,2‐Diarylethanols by Alternative Regioselective Reductive Ring‐Opening of 2,3‐Diaryloxiranes
No full textChemInform Abstract: 1,2‐Diarylethanols by Alternative Regioselective Reductive Ring‐Opening of 2,3‐Diaryloxiranes.
No full textNew Aniline‐Containing Amino Alcohols from trans‐(R,R)‐2‐(2‐Nitrophenyl)‐3‐phenyloxirane as Useful Intermediates for the Synthesis of Chiral Ligands, Bases, and Benzoxazine Nucleus.
No full textA Mild Stereo‐ and Enantiospecific Conversion of 2,3‐Diaryl‐Substituted Oxiranes into 2,2‐Dimethyl‐1,3‐Dioxolanes by an Acetone/Amberlyst 15 System
No full textNew Aniline-Containing Amino Alcohols from <i>trans</i>-(<i>R</i>,<i>R</i>)-2-(2-Nitrophenyl)-3-phenyloxirane as Useful Intermediates for the Synthesis of Chiral Ligands, Bases, and Benzoxazine Nucleus
No full textNew enantiopure aniline-containing amino alcohols are
directly derived from trans-(R,R)-2-(2-nitrophenyl)-3-phenyloxirane, by alternative regioselective double reductions.
Subsequent selective alkylation procedures and derivatizations provide a rapid and high-yielding access to different
chiral ligands, bases, and benzoxazines, without loss of
optical purity
