Synthesis and biological activity of certain 6-substituted and 2,6-disubstituted 2'-deoxytubercidins prepared via the stereospecific sodium salt glycosylation procedure

1985 ◽  
Vol 28 (10) ◽  
pp. 1461-1467 ◽  
Author(s):  
Howard B. Cottam ◽  
Zygmunt Kazimierczuk ◽  
Stewart Geary ◽  
Patricia A. McKernan ◽  
Ganapathi R. Revankar ◽  
...  
1993 ◽  
Vol 58 (9) ◽  
pp. 2159-2179 ◽  
Author(s):  
Miroslav Otmar ◽  
Ivan Rosenberg ◽  
Milena Masojídková ◽  
Antonín Holý

[5-(Adenin-9-yl)-5-deoxypentofuranosyl]phosphonates, a new type of nucleotide analogs with fixed HPMPA structure, have been prepared. The synthesis of compounds of L-arabino (IIa, IIb), D-arabino(XIVa, XIVb), 2-deoxy-L-erythro(IIIa, IIIb) and 2-deoxy-L-threo(IVa, IVb) configuration is based on the Michelis-Arbuzov reaction of the fully protected methyl glycosides with triethyl phosphite and trimethylsilyl triflate which leads to anomeric mixture of diethyl (L-pentofuranosyl) phosphonates. The protected 5-O-tosyl derivatives react with sodium salt of adenine to give N9-substituted products which after total deprotection afforded the tittle nucleotide analogs. The fixation of the partial structure of HPMPA to form five-membered ring leads to a significant decrease, or a total loss, of biological activity.


2003 ◽  
Vol 14 (4) ◽  
pp. 183-194 ◽  
Author(s):  
Stefano Manfredini ◽  
Nicola Solaroli ◽  
Angela Angusti ◽  
Federico Nalin ◽  
Elisa Durini ◽  
...  

Continuing our investigations on inhibitors of ribonucleotide reductase (RNR), the crucial enzyme that catalyses the reduction of ribonu-cleotides to deoxyribonucleotides, we have now prepared and evaluated 5′-phosphonoacetic acid, amide and ester analogues of adenosine, uridine and cytidine with the aim to verify both substrate specificity and contribution to biological activity of diphosphate mimic moieties. A molecular modelling study has been conducted on the RNR R1 subunit, in order to verify the possible interaction of the proposed bioisosteric moieties. The study compounds were finally tested on the recombinant murine RNR showing a degree of inhibition that ranged from 350 μM for the UDP analogue 5′-deoxy-5′- N-(phosphon-acetyl)uridine sodium salt (amide) to 600 μM for the CDP analogue 5′- O-[(diethyl-phosphon)acetyl]cytidine (ester). None of the tested compounds displayed noteworthy cytostatic activity at 100–500 μM concentrations, whereas ADP analogue 5′- N-[(diethyl-phosphon) acetyl]adenosine (amide) and 5′-deoxy-5′- N-(phos-phon-acetyl)adenosine sodium salt (amide) showed a moderate inhibitory activity (EC50: 48 μM) against HSV-2 and a modest inhibitory activity (EC50: 110 μM) against HIV-1, respectively.


Author(s):  
G. Kasnic ◽  
S. E. Stewart ◽  
C. Urbanski

We have reported the maturation of an intracisternal A-type particle in murine plasma cell tumor cultures and three human tumor cell cultures (rhabdomyosarcoma, lung adenocarcinoma, and osteogenic sarcoma) after IUDR-DMSO activation. In all of these studies the A-type particle seems to develop into a form with an electron dense nucleoid, presumably mature, which is also intracisternal. A similar intracisternal A-type particle has been described in leukemic guinea pigs. Although no biological activity has yet been demonstrated for these particles, on morphologic grounds, and by the manner in which they develop within the cell, they may represent members of the same family of viruses.


Author(s):  
John L. Beggs ◽  
John D. Waggener ◽  
Wanda Miller

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.


2020 ◽  
Vol 8 (38) ◽  
pp. 13368-13374
Author(s):  
Muhammad Umair Khan ◽  
Gul Hassan ◽  
Jinho Bae

This paper proposes a novel soft ionic liquid (IL) electrically functional device that displays resistive memory characteristics using poly(acrylic acid) partial sodium salt (PAA-Na+:H2O) solution gel and sodium hydroxide (NaOH) in a thin polydimethylsiloxane (PDMS) cylindrical microchannel.


2002 ◽  
Vol 23 (1) ◽  
pp. 79-121 ◽  
Author(s):  
Kathleen Taubert ◽  
Susanne Kraus ◽  
Bärbel Schulze

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
E Spilioti ◽  
B Holmbom ◽  
P Moutsatsou
Keyword(s):  

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