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1
Content available Krótka historia niektórych wzorów
Kroszczyński W.
Wiadomości Chemiczne
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2013
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[Z] 67, 7-8
733--749
EN
This article is an attempt to present how the classical detective work has been performed in order to determine chemical structures. In the past, discussion on these examples was the way of learning of the organic chemistry. Thermal degradation was the main method of analysis currently replaced with the spectroscopy. Perhaps the history of chemistry may help to understand mentalities of creators of new branches of science. On the other hand, it gives arguments for a cultivation of „impractical” sciences. The article describes the earliest attempts to present simple organic formulas undertaken by Couper and Kekulé. Examples of a transformation of aromatic compounds present how results of derivatization led to conclusions concerning structures. Experiments and logic line of thought was supported by a great intuition. More complicated molecules were investigated by degradation reactions. For example, A. Baeyer at the beginning of his investigations concerning indigo, subjected isatin (obtained from indigo by oxidation) to different reducing reagents. He obtained indoldiol, oxindole, indole etc. Then these relatively simple compounds were synthesized and served as by-products for indigo. Some methods of the industrial production of indigo were elaborated on the base of works of Baeyer [16–20]. Similarly, the structures of chrysin, brazilin and haematoxilin have been resolved mainly by their degradation. The final structures were confirmed by synthesis.
2
Assessment of pollution by heavy metals and polycyclic aromatic hydrocarbons of surface water in Kampinos National Park
Oprządek K., Syrocka K., Kluska M., Kroszczyński W., Zalewski W.
Archiwum Ochrony Środowiska
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2004
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Vol. 30, no. 3
27--34
EN
Some natural and anthropogenic properties of surface water were investigated in National Park of Kampinos in years 2000-2002. Obtained results were compared with corresponding standards. Analyses of samples of water revealed most of them to be adequate to the 1 class of purity. Benzo(a)pyrene was not detected. However, in two cases high concentration of iron and manganese was observed. As a rule, the samples collected in November exhibited higher concentration of manganese. In one case high concentration of nitrates was determined. Most of samples collected in Aleksandrów met the requirement for the II class of purity because of phosphate concentration.
PL
W latach 2000-2002 badano niektóre naturalne i antropogenne właściwości wód powierzchniowych Kampinoskiego Parku Narodowego. Uzyskane wartości średnie omówiono w porównaniu do odpowiednich norm. Analizy większości próbek wykazały, że odpowiadają one I klasie czystości. Benzo(a)pirenu nie wykryto. Jednak w dwóch przypadkach zaobserwowano wysokie stężenie żelaza i manganu. Próbki pobrane w listopadzie zawierały więcej manganu. W jednym przypadku oznaczono wysokie stężenie azotanów. Większość próbek pobranych w Aleksandrowie odpowiadała 11 klasie czystości ze względu na zawartość fosforanów.
3
Content available remote Gas-liquid chromatographic analysis of the neutral fraction obtained from elder
Olszewska E., Kroszczyński W., Łopuszyńska B.
Acta Chromatographica
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2004
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No. 14
237-240
EN
Gas–liquid chromatography has been used to investigate the neutral fraction obtained from the fruits of elder. The fraction contained vanillin and numerous unidentified compounds. Identities are suggested for some of these compounds.
4
Content available remote Ocena składu chemicznego wód podziemnych w kilku miejscowościach okolic Siedlec
Kluska M., Kroszczyński W., Oprządek K.
Chemistry-Didactics-Ecology-Metrology
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2003
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R.8, NR 1-2
53--57
PL
W latach 1992-1995 i 1999-2000 badano niektóre naturalne i antropogenne właściwości wód podziemnych w wybranych miejscowościach okolic Siedlec. Uzyskane wartości omówiono w porównaniu do odpowiednich norm.
EN
Some natural and anthropogenic properties of underground water in four selected localities in the neighbourhood of Siedlce have been investigated in the years 1992-1995 and 1999-2000. Obtained results were compared with the Polish National Standards.
5
Content available remote 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.
6
Content available remote Resolution of the diastereoisomers of prednisolone tetrahydrophthalate by chromatographic methods
Olszewska E., Kroszczyński W., Łypacewicz M., Wasiak T.
Acta Chromatographica
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2002
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No. 12
219-225
EN
The tetrahydrophthalic ester of prednisolone C29H36O8, which is used as a anti-inflammatory drug, consists of two diastereoisomers. This paper describes the effect of addition of optically active compounds (amino acids, cyclodextrin, camphosulphonic acid) on the capacity ratios, k', and separation factors, ?, of these diastereoisomers in TLC and HPLC.
7
Content available remote Gas-liquid chromatographic analysis of acids obtained from elder and dandelion
Kroszczyński W., Olszewska E., Świętulska M., Trętowska J.
Acta Chromatographica
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2002
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No. 12
89-94
EN
Gas chromatography has been used for identification of fatty acids in the leaves of elder and dandelion, in the fruits of elder, and in the roots of dandelion. Acid fractions were isolated by formation of insoluble salts or by ion exchange; methyl esters were then prepared. Some of the acids identified have not previously been reported as constituents of these tissues of elder (e.g. succinic acid, nonanedioic acid) or dandelion (e.g. 5-oxoproline, 9-oxononanoic acid), although some have already been found in other parts of the plants (e.g. in the flowers).
8
Zawartość niektórych policyklicznych węglowodorów aromatycznych w pobliżu dróg o dużym natężeniu ruchu
Kluska M., Kroszczyński W.
Chemia i Inżynieria Ekologiczna
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2000
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Vol. 7, nr 6
563-573
PL
W latach 1998-1999 badano zawartość policyklicznych węglowodorów aromatycznych w glebie, babce szerokolistnej i mniszku lekarskim w odleglości do 1 m od jezdni na terenie Siedlec przy ulicach: Warszawskiej i Brzeskiej. Analizę przeprowadzono za pomocą wysokosprawnej chromatografii cieczowej w odwróconych fazach.
EN
The content of polycyclic aromatic hydrocarbons has been investigated in samples of soil, plantain and dandelion taken along streets of city Siedlce with intensive car traffic at the distance up to 1 m from the edge of roads. The analysis was carried out by reverse phase HPLC.
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