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Wyświetlanie 1-6 z 6
Tytuł:
Naturalne i syntetyczne laktony o aktywności przeciwnowotworowej i przeciwdrobnoustrojowej
Natural and synthetic lactones with anticancer and antimicrobial activity
Autorzy:
Mazur, M.
Powiązania:
https://bibliotekanauki.pl/articles/171876.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
laktony aktywne biologicznie
laktony seskwiterpenowe
aktywność przeciwnowotworowa
aktywność przeciwdrobnoustrojowa
biologically active lactones
sesquiterpene lactones
anticancer activity
antimicrobial activity
Opis:
Medicine is one of the most developing branches of knowledge. But even now there are still some diseases which are impossible to cure. Different cancers, antibiotic resistant bacterial infections and fungal pathogenesis infections are still everlasting problems. Thus, two ways of solutions are proposed. First is the return to natural medicines. From the ancient times plants have been used in medicine and the natural products have been an important source of drugs. Nowadays isolation and identification of these compounds, together with the determination of their biological activity, also play an important role. Lactones are the cyclic esters with a wide range of carbon atoms in a lactone ring. They are a very interesting group of compounds which reveal a wide spectrum of biological activity. Terpenoid, especially sesquiterpene lactones and coumarin derivatives, are found in plants of the Asteraceae and Apiaceae families as well as in many others organisms. The naturally occurring lactones often possess anti-inflamatory [1, 2], phytotoxic [3, 4], antiprotozoal [5], and antiviral activities [6]. They are also well known for their anticancer [7, 8] and antimicrobial activities [9, 10]. The second way of obtaining new biologically active lactones is the chemical synthesis of new potent structural analogs of natural bioactive compounds. However, the complexity of natural products and their derivatives may lead to limited supplies, especially when they have the chiral centers which are one of the most important factors influencing their biological activity. It also causes difficulties to determine the mechanism of action. For those reasons, structural simplification plays an important role in the development of analog design. This review is focused on novel literature data about synthetic and natural lactones which reveal anticancer, antibacterial and antifungal activities. Presented compounds show potent biological activity and high selectivity with holding promises for further applications.
Źródło:
Wiadomości Chemiczne; 2011, 65, 1-2; 135-149
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synteza oraz aktywność antyfidantna laktonów
Synthesis and antifeedant activity of lactones
Autorzy:
Mazur, Marcelina
Powiązania:
https://bibliotekanauki.pl/articles/27310040.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
lactones
antifeedants
food deterrents
insect pests
laktony
antyfidanty
deterenty pokarmowe
szkodniki owadzie
Opis:
Antifeedants, or food deterrents, are substances that, by acting on the sense of taste of insects, entirely or partially inhibit their feeding and can be used to reduce the population of harmful species. Antifeedants have the advantage of low toxicity and high selectivity towards selected groups of pests, providing an alternative to the classically used insecticides, which usually have a broad spectrum of action and greater toxicity, even towards vertebrates. Among their numerous activities, lactones can exhibit antifeedant properties. However, the use of natural lactones as antifeedants is limited due to their low isolation yields from natural sources and complex chemical synthesis. Therefore accesible synthetic compounds are of great interest. This work presents the synthesis pathways and the deterrent activities of the lactones obtained in convenient transformations, often from natural terpene precursors.
Źródło:
Wiadomości Chemiczne; 2023, 77, 5-6; 533--554
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synergistyczne działanie flukonazolu i laktonów ftalidowych jako czynnik ograniczający stosowanie leków azolowych w leczeniu kandidoz
Synergistic effect of fluconazole and phtalide lactones as a factor limiting the use of azole drugs against candidiasis
Autorzy:
Olejniczak, Teresa
Powiązania:
https://bibliotekanauki.pl/articles/27310047.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
efekt synergii
Candida albicans
laktony ftalidowe
flukonazol
synergistic effect
phthalide lactones
fluconazole
Opis:
The resistance of Candida albicans and other pathogenic yeasts to azole antifungal drugs has increased rapidly in recent years and is a significant problem in clinical therapy. The current state of pharmacological knowledge precludes the withdrawal of azole drugs, as no other active substances have yet been developed that could effectively replace them. Therefore, one of the anti-yeast strategies may be therapies that can rely on the synergistic action of natural compounds and azoles, limiting the use of azole drugs against candidiasis. Synergy assays perperformed in vitro were used to assess drug interactions Fractional Inhibitory Concentration Index. The synergistic effect of fluconazole (1) and three synthetic lactones identical to those naturally occurring in celery plants—3-n-butylphthalide (2), 3-n-butylidenephthalide (3), 3-n-butyl-4,5,6,7-tetrahydrophthalide (4)—against Candida albicans ATCC 10231, C. albicans ATCC 2091, and C. guilliermondii KKP 3390 was compared with the performance of the individual compounds separately. MIC90 (the amount of fungistatic substance (in µg/mL) inhibiting yeast growth by 90%) was determined as 5.96–6.25 µg/mL for fluconazole (1) and 92–150 µg/mL for lactones 2–4. With the simultaneous administration of fluconazole (1) and one of the lactones 2–4, it was found that they act synergistically, and to achieve the same effect it is sufficient to use 0.58–6.73 µg/mL fluconazole (1) and 1.26–20.18 µg/mL of lactones 2–4. Based on biological research, the influence of the structure on the fungistatic activity and the synergistic effect were determined.
Źródło:
Wiadomości Chemiczne; 2023, 77, 5-6; 555-567
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Otrzymywanie i właściwości biologiczne racemicznych i optycznie czynnych laktonów z pierścieniem aromatycznym w pozycji β
Synthesis and biological properties of racemic and optically active lactones with aromatic ring on β-position
Autorzy:
Gładkowski, Witold
Powiązania:
https://bibliotekanauki.pl/articles/27310041.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
laktony
synteza chemoenzymatyczna
konfiguracja absolutna
aktywność antyproliferacyjna
aktywność antyfidantna
lactones
chemoenzymatic synthesis
absolute configuration
antiproliferative activity
antifeedant activity
Opis:
Natural and synthetic lactones containing an aromatic ring exhibit a number of biological properties, e.g. antiproliferative, antifeedant or antimicrobial activity. This review deals with the synthesis and biological properties of lactones containing an aromatic substituent in the β-position of the lactone ring. The described group of compounds includes halolactones, hydroxylactones, unsaturated lactones and products of reductive dehalogenation of iodolactones. In addition to chemical transformations, biotechnological methods for obtaining optically active lactones have also been described, including the use of lipases in the chemoenzymatic pathway leading to the production of halolactones, kinetic separation of hydroxylactones in the process of enzymatic transesterification, microbial hydrolytic dehalogenation of iodolactones and enantioselective hydrolysis of the lactone ring. The biological activity of the obtained β-aryllactones was also briefly characterized.
Źródło:
Wiadomości Chemiczne; 2023, 77, 5-6; 509--531
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dwie dekady chemo-enzymatycznej reakcji Baeyera-Villigera
Two decades of chemo-enzymatic Baeyer-Villiger reaction
Autorzy:
Drożdż, A.
Bielas, R.
Chrobok, A.
Powiązania:
https://bibliotekanauki.pl/articles/171768.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
reakcja Baeyera-Villigera
chemo-enzymatyczna reakcja Baeyera-Villigera
laktony
utlenianie cyklicznych ketonów
lipaza B Candida antarctica
chemo-enzymatic Baeyer–Villiger reaction
lactones
cyclic ketones oxidation
lipase B Candida antarctica
Opis:
The Baeyer–Villiger oxidation of ketones to lactones or esters is a reaction of significant interest in organic chemistry owing to very wide range of possible applications, e.g. in the synthesis of antibiotics, steroids, pheromones and monomers for polymerisation. The organic percarboxylic acids typically used as oxidants in these reactions are fairly expensive, often poorly stable and hazardous, and this consequently limits their commercial application. Therefore, the chemo-enzymatic approach appears to be a very attractive alternative. The paper presents literature reports concerning the application the use of lipase B from Candida antarctica in the chemo-enzymatic Baeyer-Villiger oxidation. It involves oxidation of long- or medium-chain carboxylic acids with H2O2 or urea hydrogen peroxide to generate in situ peracid which is later used to oxidise ketones to lactones.
Źródło:
Wiadomości Chemiczne; 2014, 68, 11-12; 1031-1048
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synteza γ-laktonów z podstawnikami aromatycznymi
Synthesis of γ-lactones with aromatic substituents
Autorzy:
Skrobiszewski, A.
Gładkowski, W.
Powiązania:
https://bibliotekanauki.pl/articles/171624.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
gamma laktony
pierścienie aromatyczne
reakcja Suzuki-Miyaury
enzymatyczna estryfikacja i hydroliza
mikrobiologiczna redukcja grupy karbonylowej
diastereoselektywne alkilowanie
enancjoselektywne uwodornienie podwójnego wiązania
gamma-lactones
aromatic rings
Suzuki-Miyaura reaction
enzymatic hydrolysis and acetylation
microbial reduction of a carbonyl group diastereoselective alkylation
enantioselective hydrogenation of olefinic substrates
Opis:
Biological activities of lactones are predominantly determined by different substituents on a lactone ring. γ-Lactones with aromatic substituents have interesting biological activities and serve as useful intermediates in the synthesis of many natural and synthetic products. Pulvinic and vulpinic acids exhibit antimicrobial, antioxidant and anticancer activity [1–3]. Paraconic acids have anticancer and antibacterial activity [4, 5]. The interesting biological activities i.a. antileukemic, anti- HIV and cytostatic, have been found for dibenzyl-γ-lactones [8]. This review covers some examples of synthetic and biotechnological methods leading to either racemic or optically active γ-lactones with aromatic substituents. The racemic α-benzylidene lactones can be produced from Baylis-Hillman acetates [9]. The multicomponent synthesis of the paraconic acid analogs is performed by a fourfold metallation-conjugate addition-aldol addition-intramolecular transesterification sequence [4]. Suzuki-Miyaura reaction is the key step in the synthesis of asymmetric pulvinic acids [1]. Some other examples of synthetic strategies involving the reactivity of ylides, vicinal dianions, ozonolysis or Claisen rearrangement are also presented [10–13]. Production of optically active γ-lactones with aromatic substituents involves application of biotechnological and chemical methods. The first one includes using commercially available enzymes [16, 17] or whole cells of microorganisms [18–20]. Chemical methods involve application of chiral starting materials like malic acid esters or the derivatives of succinic acid [14, 15] or chiral catalysts like BINAP-Rh or Ru complexes [7].
Źródło:
Wiadomości Chemiczne; 2013, 67, 9-10; 943-960
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-6 z 6

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