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1

Środki ochrony roślin o budowie chiralnej

Morzycka B., Morzycki J. W.

Wiadomości Chemiczne

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2003

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[Z] 57, 9-10

855--876

EN

The agrochemical industry is continuously searching for new active compounds to combat pests. The main aim of this research is to develop new substances with lower application rates, increased selectivity and decreased undesired ecological impact. Most synthetic agrochemicals with chiral structure are marketed as racemates even though the desired biological activity may be derived from only one enantiopure isomer. However, some newly introduced compounds are marketed as the most biologically active stereoisomers. When agrochemicals have chiral structures, efforts should be made to define the mode of action, toxicity, and metabolic pathway of each enantiopure isomer. If there are large differences in the biological activities of individual stereoisomers, it is desirable to use only the most active one. In this review article some stereochemical aspects of several groups of important agrochemicals including aryloxypropanoate herbicides, acylanilides, triazine herbicides, ureas and cyanoacrylates, triazole fungicides, morpholine derivatives, organochlorine insecticides, pyrethroid insecticides, pheromones and antifeedants, and organophosphorus compounds, will be discussed.

2

Nie kończąca się historia witaminy D

Kroszczyński W., Morzycka B., Morzycki J.W.

Wiadomości Chemiczne

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2002

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[Z] 56, 9-10

793-809

EN

The existence of vitamin D was discovered as a consequence of human disease. Vitamin D deficiency in childhood produces rickets, which is characterized by inadequate calcification of cartilage and bone. In rickets, the whole bony structure is soft and flexible, so that can hardly support the superposed weight of the body. Rickets was common in the 19th century, when the industrial revolution caused change of an agrarian society to an industrial society. The population in large measure spent much more time inside buildings, which shielded them from ultraviolet light. It was proved that sun light and cod liver oil are equally active in preventing and curing rickets. Further studies led to the discovery of an anti-rachitic vitamin D. A deficiency in vitamin D impairs bone formation in growing animals. The precursor of cholecalciferol (vitamin D3) is 7-dehydrocholesterol (provitamin D3) present in the skin. Irradiation of this compound results in the formation of previtamin D3, which spontaneously isomerizes to vitamin D3 (thermal rearrangement). Vitamin D3 is further converted by enzymatic hydroxylation reactions occurring in the liver and kidneys into an active hormone, which was isolated and identified as 1a,25-dihydroxyvitamin D3. Other biologically active metabolites and analogues of vitamin D were also described. The vitamin D endocrine system was primarily recognized for its critical role in calcium and phosphorus homeostasis. The active form of the vitamin, 1a,25-(OH) 2D3, acts on the intestine, bone, and kidney to increase serum levels of these two elements. Receptors for 1a,25-(OH) 2D3 have also been detected in a wide variety of target tissues and cell types, which are not involved in the calcemic activity. The non-classical actions of 1a,25-(OH) 2D3 have suggested a multitude of potential therapeutic applications of the vitamin D hormone for the treatment of hyperproliferative disorders (e.g. cancer and psoriasis), immune dysfunction and endocrine disorders. A number of new drugs based on the vitamin D analogues has been recently introduced to the pharmaceutical market. The story of vitamin D is not finished yet.

3

Multiresidue matrix solid-phase dispersion method for the determination of fungicides in fruits and vegetables

Morzycka B.

Chemia Analityczna

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2002

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Vol. 47, No. 4

571-583

EN

The matrix solid-phase dispersion (MSPD) method with GC detection for the determination of of residues of fourteen fungicides (azoxystrobin, bitertanol, bupirimate, captan, chlorothalonil, dichlofluanid, fenarimol, flusilazole, iprodione, metalaxyl, procymidone, pyrimethanil, tetraconazole, vinchlozolin) that are currently applied lo agricultural crops is described. The method uses Florisil and silica as MSPD sorbents. Different parameters, such as type of solid phase, eluting solvent and matrix, were investigated. Recovery checks have been carried out on different commodities (tomatoes, cucumbers, strawberries, apples, raspberries, and melons). The limits of detection were in the 0.003-0.01 mg kg(1) range and were about 10 times lower than the maximum residue limits allowed. Compared with classical methods, the procedure described is simple, rapid and economical, and may be useful for the determination of fungicides of different chemical structures. These pesticides have been detected in samples taken from the fields at levels of 0.006-4.295 mg kg(-1).

PL

Opisano metodę rozproszenia matrycy w fazie stałej (MSPD) z detekcją GC w zastosowaniu do oznaczania pozostałości czternastu fungicydów (azoksystrobiny, hitertanolu, bupirymatu, chlorotalonilu, dichlofluanidu, fenaritnolu, flusilazolu, iprodionu. kaptanu, metalaksylu, pirymetanilu, procymidonu, tetrakonazolu, winchlozoliny), które są obecnie stosowane w rolnictwie do ochrony owoców i warzyw przed chorobami grzybowymi. W metodzie użyto Florisilu i żelu krzemionkowego jako adsorbentów. Badano parametry, takiejak typ fazy stałej, eluent i rodzaj matrycy. Odzysk metody sprawdzano na próbkach różnych owoców i warzyw (pomidory, truskawki, jabłka, maliny i melony). Wykrywalność oznaczanych związków mieściła się w zakresie 0.003-0.01 mg kg(1) i była około 10 razy niższa niż ich najwyższy dopuszczalny poziom. W porównaniu z metodami klasycznymi, opisana procedura jest prosta, szybka, ekonomiczna i może być używana do oznaczania tungicydów o różnych strukturach chemicznych. Pestycydy w próbkach pobranych z pól wykrywano w zakresie 0.006-4.295 mg kg(-1).