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Distribution of nitrogen compounds in important sections of sugar beets

Bąk P., Antczak-Chrobot A., Wojtczak M.

Biotechnology and Food Science

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2016

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Vol. 80, nr 1

53--61

EN

In literature the beet is often described as consisting of the following technologically important sections: crown, root and tail. The aim of the study was to determine the distribution of nitrogen compounds in the technologically important beet sections of untopped sugar beets with particular emphasis on the content of nitrate and nitrite. The Finezja sugar beet variety had been collected from the clamps in one of the Polish sugar factories in October during 2013/2014 campaign. The untopped sugar beets were divided into three sections: crown, root and tail. The content of total amount of nitrogen, proteinaceous nitrogen, α-amino nitrogen, the sum of the amide and ammonia nitrogen, nitrates and nitrite in these sections were determined. Although the crown of the sugar beet represented only 14.7% of it mass, this section contained on average 30% of the total quantity of α-amino acids as well as amide and ammonia nitrogen.This section contained approximately 77% of the total quantity of nitrate and 88% of nitrite. Untopped sugar beets would introduce much higher amounts of nitrogen compounds in comparison to topped raw material.

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Asymetryczna synteza α, β-diaminokwasów

Błaszczyk R., Gajda T.

Wiadomości Chemiczne

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2009

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[Z] 63, 7-8

635-684

EN

Through the years, α,β-diamino ac6ds and their derivatives have attracted a great deal of attention among organic chemists because of their biological significance [1, 2]. This review deals with the synthetic approaches of α,β-diamino acids and their derivatives (e.g., esters, amides) using asymmetric synthesis methods described in the literature up to the end of 2008. Aziridines and 3-amino-β-lactams are beyond the scope of this review and will be only considered as intermediates in the synthesis of acyclic derivatives. The methods found in the literature can be classified essentially in two main categories: methods that require a new carbon-carbon single bond construction and method based on the functional groups transformation reactions within the carboxylic acids skeleton. A great number of C-C forming methods are the addition reactions of glycine derivatives or nitro compounds to imines (Mannich-type reactions). The asymmetric induction requires chiral substrate usage (e.g., chiral sulfinimines, chiral glycinates) [30-37, 61-67] or results from the application of chiral catalysts (e.g., chiral Lewis acids, chiral PTC catalysts and other organocatalysts) [39-48, 50-60] . Strecker's reaction using chiral imines or related compounds is also often used [69-77]. Methods begining from the existing carbon skeleton and based on the modification of the functional groups are as follows: catalytic asymmetric diamination and aminohydroxylation of α,β-unsaturated carboxylic esters [92-100, 107-109]. Subsequent transformation of the hydroxy group into the amine group in the hydroxyamino acids derivatives is then necessary [100-109]. The direct introduction of the amino moiety into the β-amino esters via electrofilic amination is also described [120-131]. The title compounds can also be obtained by catalytic enantioselective reduction of dehydrodiamino acids derivatives[117-119].

3

Nowe monomery do syntezy poli(estroimidów)

Borycki J., Wilczek M., Kolendo A. Y.

Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje

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2003

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Vol. 52, nr 25

616-619

PL

Przedstawiona praca stanowi pierwszy etap syntezy optycznie czynnych poli(estroimidów). Tego typu polimery zawierające ugrupowanie imidowe, mogą być otrzymane z optycznie czynnych kwasów dikarboksylowych z glikolami lub bisfenolami. Przeprowadzono syntezy nowych, opytcznie czynnych kwasów dikarboksylowych z bezewodników kwasowych: trimelitowego (TDA), piromelitowego (PMDA), benzofenowego-3,3',4,4'-tetrakarboksylowego (BDTA) z optycznie czynnymi aminokwasami: L-alaniną (L-Ala), D-alaniną (D-Ala), L-waliną (L-Val), kwasem L-2-amino-masłowym (L-Abu). Oznaczono temperaturę topnienia otrzymanych związków oraz wykonano ich widma rezonansu protonowego (1 H NMR) oraz IR.

EN

The dicarboksylic acids containing imide groups, not reported yet in literature, were prepared by reacting anhydrides with optically active a(alpha)-aminoacids. They can be used for the syntheis of optically active poly(esther imide)s and poly(amide imide)s.