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N-(E)-2-Stilbenyloxymethylenecarbonyl substituted hydrazones of ortho, meta and para hydroxybenzaldehydes

Wyrzykiewicz E., Błaszczyk A., Turowska-Tyrk I.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 3

213-229

EN

Twelve unknown N-(E)-2-stilbenyloxymethylenecarbonyl substituted hydra-zones of acetone and ortho, meta and para hydroxybenzaldehydes have been prepared. The N-substituted hydrazones occur as E geometrical isomers and cis/trans amide conformers (1) H NMR estimations). Crystal structures of N-(E)-2-stilbenyloxymethylenecarbonyl sub-stituted hydrazone of ortho hydroxy-benzaldehyde 10 and N-(E)-2/-(4/-chlorostilbenyloxy-methylenecarbonyl)-substituted hydrazone of meta hydroxybenzaldehyde 14 have been determined as E geometrical isomers and trans amide conformers with intra- (10) and intermolecular (14) hydrogen bonds.

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Metody syntezy siarkowych pochodnych zasad pirymidynowych

Nowakowska Z., Wyrzykiewicz E.

Wiadomości Chemiczne

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1998

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[Z] 52, 5-6

449-466

EN

Uracil thio-derivatives have become to play increasingly important roles in biology and medicine. Numerous sulphur-substituted pyrimidines have found applications as clinically useful drugs. Thiouracils have recently been the subject of considerable interest as they inhibit hyperthyroidism in man [1, 2], have been isolated from E. Coli tRNA [3], and inhibit virus [4] and bacterial growth [5] by causing alterations [6] in protein synthesis. Thiouracils are also of interest because of mutagenic [7], anticancer and antithyroid activity [8], kidney stone formation inhibition [9] and antidote properties for mercury poisoning . Two of them, 2-thiouracil and 6-propyl-2-thiouracil, exhibit marked affinities for melanin-producing tissue in vitro and a similar affinity in vivo, where they presumably act as false precursors for melanin [10, 11]. Boron-containing derivatives of thiouracils [12-14] containing a dihydroxyboryl (or 1-o-carboranylalkyl) group in the 5-position are very important because of their potential applications for BNCT. Human immunodeficiency virus type 1 (HIV-1) is the causative agent of acquired immunodeficiency syndrome (AIDS), which is one of the world's most serious health problems. Since the discovery of the acyclic 6-substituted uridine derivative 1-[(2-hydroxyethoxy0methyl]-6-(phenythio)-thymine (HEPT) as a novel lead for specific anti-HIV-1 agents [15], a number of HEPT analogs have been synthesized to increase its potency [16-18]. The studies of the structure-activity relationships of HEPT analogs indicated that replacement of the 2-oxo function with a thine function potentiated their anti-HIV-1 activity [16, 19, 20]. Therofore the synthesis of thio-substituted pyrimidine bases and their derivatives appears to be a challenge for organic chemists. The methods of preparation of these compounds have been reviewed.

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New isomeric N-substituted hydrazones of ortho, mata and para hydroxybenzaldehydes

Wyrzykiewicz E., Prukała D.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 4

694-702

EN

27 unknown N-(E)-stilbenyloxyalkylcarbonyl- and N-(E)-stilbenyloxyalkylcarbonylaminoalkylcarbonyl- substituted hydrazones of ortho, meta and para hydroxybenzaldehydes were prepared. From (1)H-NMR(inDMSO-d-6) was established that the N-substituted hydrazones occurred as E geometrical isomers and cis/trans amide conformers.