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Wyświetlanie 1-3 z 3
Tytuł:
Bioaktywne N-acyloamidofosforanowe pochodne nukleozydów
Bioactive N-acylphosphoramidate nucleoside derivatives
Autorzy:
Kulik, K.
Powiązania:
https://bibliotekanauki.pl/articles/172366.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
ugrupowanie N-acyloamidofosforanowe
analogi aminoacyloadenylanów
analogi nukleozydów
Fosmidozyna
N-acylphosphoramidate function
aminoacyl adenylate analogues
nucleoside analogues
Phosmidosine
Opis:
Natural nucleotide antibiotics such as Agrocin 84, Dinoguellin, Microcin C and Phosmidosine have a N-acylphosphoramidate linkage at the 5’-hydroxyl of the adenosine derivatives (Fig. 1, 2) [1–3]. They exhibit interesting antifungal, antiemetics and anticancer properties. To synthesize these products, the construction of the N-acylphosphoramidate linkages seems to be a key step. Many groups have described the preparation of such a type of analogues but none of those methods was general. Grandas has for the first time reported the synthesis, of N-acylphosphoramidate peptide-oligonucleotide hybrids via condensation of N-phosphitylated carboxyamides with alcohols in the presence of 1H-tetrazole [9]. Based on this strategy Sekine synthesized aminoacyl adenylate (aa-AMP) analogues which could be useful in the studies on the recognition mechanism of the aminoacylation of tRNA and other biochemical reactions [10]. Since aa-AMPs are extremely unstable under aqueous conditions more stable analogues were required. Aminoacyl-adenylate analogues having an N-acylphosphoramidate linkage (aa-AMPN) could behave as potent, selective asparagine synthetase (AS) inhibitors because of its structural similarity to β-aspartyl-AMP (β AspAMP) which is natural product of AS [17]. Among natural N-acylphosphormiadates, Phosmidosine which connects a nucleoside analogue, 8-oxoadenosine, with an L-proline residue is unique because of its significant antitumor activities and property of stopping cell growth at the G1 phase in the cell cycle (Fig. 2) [2, 13]. The main difficulty during the synthesis of this compound is an extreme instability under weak basic conditions which excludes the use of labile protecting group of basic properties [14]. Stability studies have shown that under basic conditions phosphoryl group of Phosmidosine underwent rapid N–N migration (Scheme 9) [16]. Many modifications have been introduced to improve Phosmidosine properties [16]. Analogues such as demethylated species (Phosmidosine B) have proven to be stable under both basic and acid conditions and are also potential candidates for antitumor drugs [14].
Źródło:
Wiadomości Chemiczne; 2013, 67, 9-10; 877-897
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adenozyno-5’-o-(n-acylosulfamoilowe) pochodne jako potencjalne leki przeciwgruźlicze
5’-o-[n-(acyl)sulfamoyl]adenosine derivatives as potential antituberculosis drugs
Autorzy:
Kulik, K.
Baraniak, J.
Powiązania:
https://bibliotekanauki.pl/articles/172072.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
leki przeciwgruźlicze
prątek gruźlicy
acyloadenylany
antituberculosis drugs
Mycobacterium tuberculosis
acyladenylates
Opis:
Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis (TB), is the leading bacterial cause of infectious disease mortality. The current WHOapproved treatment for TB involves a three- or four-drug regimen comprising isoniazid, rifampin, pyrazinamide, and/or ethambutol for a minimum of 6 months. While these first-line agents remain useful in treating susceptible Mycobacterium tuberculosis strains, the emergence of multidrug resistant tuberculosis demands the development of new drugs [1]. Iron acquisition is an essential process for M. tuberculosis as well as almost all other microorganisms. However, this essential micronutrient is highly sequestered in a mammalian host. In response to iron starvation, Mtb produces small-molecule iron chelators, a pair of related peptidic siderophores known as mycobactin and carboxymycobactins that vary by the appended lipid residue termed siderophores [4, 5, 7, 8]. Because mycobactins are critical for growth and virulence of M. tuberculosis, they have emerged as attractive targets for the development of anti-TB agents [4]. Biosynthesis of mycobactin is initiated by the aryl acid adenylation enzyme MbtA which activates salicylic acid forming an acyladenylate intermediate (Sal- AMP). MbtA is also responsible for loading the acyladenylate intermediate onto the thiolation domain of MbtB-SH – the enzyme taking part in the next step of biosynthesis process [10]. Given the documented importance of many siderophores for virulence and lack of human aryl acid adenylation enzymes homologues, several analogues possessing stable linkers as bioisosteres of the labile acyl phosphate function have been synthesized as the potent enzyme inhibitors [13]. The initial lead compound 5’-O-[N- (salicyl)sulfamoyl]adenosine (Sal-AMS) has emerged as a promising inhibitor of MbtA and was shown to possess promising whole-cell activity toward M. tuberculosis.
Źródło:
Wiadomości Chemiczne; 2016, 70, 7-8; 455-472
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pronukleotydy o strukturze amidofosforanów i ich wewnątrzkomórkowy mechanizm aktywacji
Phosphoramidate pronucleotides and their intracellular activation mechanism
Autorzy:
Kulik, K.
Baraniak, J.
Powiązania:
https://bibliotekanauki.pl/articles/171604.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
pronukleotydy
amidofosforany
aktywność fosforoamidazowa
Hint
białko triady histydynowej wiążącej nukleotyd
prolek
pronucleotides
phosphoramidates
phosphoramidase activity
histidine triad nucleotide binding protein
prodrug
Opis:
Nucleoside analogues have great therapeutic potential for the treatment of cancer and viral diseases. Once inside the cell, they are activated by a series of intracellular phosphorylation steps to produce 5’-triphosphate derivatives, which can be incorporated to DNA or RNA and act as terminators of growing polynucleotide chains [1c]. In many cases, nucleoside analogues are poor substrates for the cellular kinases needed for their activation [5]. It is clear that intracellular introduction of nucleoside analogues as phosphorylated metabolites (so called pronucleotides) could circumvent difficulties associated with the use of non-phosphorylated nucleoside analogues and could even activate inactive compounds or could increase the activity of the nucleoside analogues. However, polarity and a ready degradation by phosphatases make the use of free nucleotide analogues impractical. Therefore, much of the recent efforts have been focused on finding suitable prodrugs of nucleoside analogue monophosphates. Among the current diverse prodrug approaches, nucleoside phosphoramidate derivatives appear to be an interesting class of antiviral and anticancer agents [1c]. These prodrugs, as are devoid of negative charge, should be able to cross the cell membrane either by diffusion or utilizing transport protein [1c]. Conducted cell extract studies have provided evidence of a bioactivation mechanism that relies on enzyme-catalyzed P-N bond hydrolysis in phosphoramidate pronucleotides [1a,b]. It was assumed that phosphoramidate derivatives should generate nucleoside monophosphates inside the cell at rates that are influenced by both the nature of the amino group and the pH of the medium. Then nucleoside monophosphates should be phosphorylated in two different steps to the corresponding 5’-O-triphosphates (NTP) which can inhibit polymerase or be incorporated into the DNA strand being synthesized in the cell. Over the last decade extensive studies has been carried out to establish the mechanism of action of phosphoramidates and identification of enzymes responsible for bioactivation this pronucleotides to phosphorylated nucleosides [7, 21, 24]. Investigation of metabolism pathways provided evidence that phosphoramidase activity of Hint (histidine triad nucleotide-binding proteins) play a key role in the activation of phosphoramidate pronucleotides [23–27].
Źródło:
Wiadomości Chemiczne; 2014, 68, 9-10; 811-831
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

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