Zobrazeno 1 - 10
of 33
pro vyhledávání: '"František Považanec"'
Publikováno v:
Tetrahedron: Asymmetry. 17:1629-1637
A new synthesis of enantiomerically highly enriched N-substituted furoylalanines has been developed. This process involves the combination of crystallisation induced asymmetric transformation (CIAT) and a conjugate addition of N-nucleophiles to furoy
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::74e03843c61d0587f2bf9c4489c06124
https://doi.org/10.1016/j.tetasy.2006.04.024
https://doi.org/10.1016/j.tetasy.2006.04.024
Publikováno v:
Tetrahedron: Asymmetry. 16:1927-1934
Acid-catalyzed lactonization in dilute hydrochloric acid of N-substituted 2-amino-4-aryl-4-hydroxybutanoic acids with electron donating aryl substituents is stereoconvergent. The stereochemical outcome is controlled by the precipitation of little sol
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a8e09e39988d35ab098684ef1970dfc7
https://doi.org/10.1016/j.tetasy.2005.04.024
https://doi.org/10.1016/j.tetasy.2005.04.024
Publikováno v:
Tetrahedron Letters. 46:975-978
CIAT of aza-Michael adducts allows simultaneous build up of two stereocenters. A consequent short and efficient synthesis affords simple access to the both antipodes of various conformationally restricted homophenylalanines.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::cf4f5d8169b770852f719755f7b8a5f9
https://doi.org/10.1016/j.tetlet.2004.12.048
https://doi.org/10.1016/j.tetlet.2004.12.048
Publikováno v:
Tetrahedron Letters. 41:5257-5260
A highly stereoselective reduction of γ-oxo-α-amino acids by sodium borohydride in the presence of a catalytic amount of manganese(II) chloride gives syn -γ-hydroxy-α-amino acids. Enantiomerically pure syn -(2 S ,4 R ,1′ S )-4-aryl-4-hydroxy-2-
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5b60e1afe35e8996f116f07bde054904
https://doi.org/10.1016/s0040-4039(00)00800-5
https://doi.org/10.1016/s0040-4039(00)00800-5
Autor:
Peter Baran, Martin Breza, Guido Kickelbick, N. Pronayova, Peter Šafář, Jozef Kožíšek, František Považanec
Publikováno v:
Scopus-Elsevier
5-[(2-Furyl)methylidene]-2,2-dimethyl-1,3-dioxane-4,6-dione (1a) treated with equimolar amount of pyrrolidine or hexahydroazepine afforded 5-(pyrrolidine)- (2a) or 5-[(hexahydro- azepine-1-yl)-2-hydroxypenta-2,4-dien-1-ylidene]-2,2-dimethyl-1,3-dioxa
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3ead4c0e9f8a8ca7c6215c91bd51cb83
https://doi.org/10.1135/cccc20001911
https://doi.org/10.1135/cccc20001911
Publikováno v:
Collection of Czechoslovak Chemical Communications. 62:1105-1113
(5-Bromo-2-furyl)methylidenemalonodinitrile (1) reacted with substituted aromatic amines under formation of (5-N-arylamino-2-furyl)methylidenemalonodinitriles 2a-2h whereas no reaction was observed with N-alkyl-N-phenylamines. Derivatives of 2-cyano-
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::c15e940143b2390c6d3f3b6dbfb9eece
https://doi.org/10.1135/cccc19971105
https://doi.org/10.1135/cccc19971105
Publikováno v:
Chemical Papers. 67
Straightforward preparation of enantiomerically highly enriched N-substituted aroylalanines has been developed. This process involves the combination of crystallization-induced asymmetric transformation and a conjugate addition of N-nucleophiles to t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a5c017cd88c691a8afd93f201c917c6f
https://doi.org/10.2478/s11696-012-0246-z
https://doi.org/10.2478/s11696-012-0246-z
Autor:
Ján Cvengroš, František Považanec
Publikováno v:
Bioresource Technology. 55:145-150
Rapeseed oil methyl esters are important alternative diesel fuels based on renewable sources. A discontinuous plant production of methyl esters (ME) is described using two-stage low-temperature transesterification of cold-pressed rapeseed oil with me
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::27e0ee77c6000e1d8bff11c87dd7a719
https://doi.org/10.1016/0960-8524(95)00190-5
https://doi.org/10.1016/0960-8524(95)00190-5
Publikováno v:
Collection of Czechoslovak Chemical Communications. 59:2481-2492
Reaction of derivatives of 2-furancarbaldehyde or 2-acetylfuran with malononitrile, methyl cyanoacetate or cyanoacetamide in the presence of secondary amines afforded derivatives of 2-amino-3-furancarboxylic acid in 45 - 88% yields.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5039cfed41612042d4cf001777ac4cbc
https://doi.org/10.1135/cccc19942481
https://doi.org/10.1135/cccc19942481
Publikováno v:
Collection of Czechoslovak Chemical Communications. 58:555-564
(E-2-Formyl-3-(2-furyl)propenenitrile (I) reacts with primary aromatic amines under formation of 3-(arylamino)-2-[5-(arylamino)-2-oxo-3-cyclopenten-1-yl]propenenitriles (IVa-IVi). Condensation of I with salts of nitrogen bases in pyridine affords 2-(
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9f59f74df4dc629135d1658ea354b4f3
https://doi.org/10.1135/cccc19930555
https://doi.org/10.1135/cccc19930555