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1
Synthesis of Complex Bicyclo[4.3.0]nonene Derivatives from Sugar Allyltins; Sugar Mimetics Derived from D-Glucose
Jarosz S., Jędra S.
Polish Journal of Chemistry
|
2009
|
Vol. 83, nr 10
1757-1764
EN
Controlled decomposition of sugar allyltin: methyl 2,3,4-tri-O-benzyl- 6,7,8- tri -deoxy-8-(tri-n-butyl)stannyl-alfa-D-gluco-oct-6(E)-eno-hexo-1,5-pyranoside af forded the corresponding dienoaldehyde with the D-xylo-configuration and the E-geometry across the internal double bond. Reaction of this intermediate with Ph3P=CH-CO2Me provided a triene, which under went cyclization to the bicyclic products: derivatives of bicyclo[4.3.0]nonatriene. Stereochemical aspects of this cyclization, as well as some transformations leading to carbobicyclic sugar mimics, are discussed.
2
Zwykły cukier, sacharoza : zastosowanie w syntezie złożonych produktów
Jarosz S.
LAB Laboratoria, Aparatura, Badania
|
2008
|
R. 13, nr 5
10-17
3
Synthesis of Octoses by Brimacombe Methodology; a Hard Proof for the Structure of the anti-Kishi Product of Osmylation of Unsaturated Ester
Jarosz S., Osuch A., Luboradzki R.
Polish Journal of Chemistry
|
2007
|
Vol. 81, nr 4
521-527
EN
Reaction of 1,2:3,4-di-O-isopropylidene--D-galactopyranos-6-ulose with Ph3P=CH-CO2Me conducted in methanol afforded exclusively the Z-,-unsaturated ester, which was further reduced with DIBAL-H to the allylic alcohol. Osmylation of the unsaturated ester afforded two stereoisomeric diols in a 4:1 ratio, with the ‘anti Kishi product’ predominating, while the same process performed on the allylic alcohol provided the expected ‘Kishi product’with high selectivity. The structure of the latterwas confirmed byX-ray analysis of its 8-O-tritylated derivative.
4
Approach to Higher Carbon Sugars Functionalized at Both Terminal Positions
Jarosz S., Gajewska A.
Polish Journal of Chemistry
|
2007
|
Vol. 81, nr 11
1949-1957
5
Synthesis of C-Glycosidic Galacturonates Suitable as Glycosyl Acceptors
Vogel C., Farouk M., Michalik M., Reinke H., Jarosz S.
Polish Journal of Chemistry
|
2005
|
Vol. 79 / nr 2
251-265
EN
Methyl 3,4,5-tri-O-acetyl-2,6-anhydro-7,8,9-trideoxy-D-glycero-L-galacto-non-8-enonate (5) was obtained by different routes starting from D-galactose and D-galacturonic acid, respectively. Exploring several protecting group manipulations, an effective route was found out for the preparation of methyl 2,6-anhydro-5-O-benzyl-7,8,9-trideoxy- D-glycero-L-galacto-non-8-enonate (15) which is one of the key compounds in this synthetic program. Finally, selective benzylation via 3,4-O-butylstannyl intermediates resulted in methyl (16) and benzyl (17) 2,6-anhydro-4,5-di-O-benzyl-7,8,9-trideoxy-Dglycero- L-galacto-non-8-enonate both suitable as acceptors in glycosylation reactions. The chemical structure of a great number of intermediates was investigated by X-ray diffraction studies.
6
Functionalization of the Homoallylic Bridge in Higher Sugar Precursors
Jarosz S., Szewczyk K., Gaweł A., Gomez A., Lopez J.
Polish Journal of Chemistry
|
2005
|
Vol. 79 / nr 2
231-238
EN
The Barton reduction of the sugar homoallylic xanthate did not afford the expected hydrocarbon, but led to two cyclic products resulting from the attack of initially formed radical onto the olefin fragment of the homoallylic system. The mechanism of such cyclization is discussed.
7
Enantiomerically Pure Carbocyclic Derivatives from Sugar Allyltins
Jarosz S.
Polish Journal of Chemistry
|
2004
|
Vol. 78 / nr 7
881-901
EN
The concise approach to enantiomerically pure, highly oxygenated carbobicyclic derivatives from sugar allyltins as well as the preparation of these sugar organometallics is reviewed.
8
Synthesis and Reactivity of Sugar Allyltin Derivatives
Jarosz S., Szewczyk K., Zawisza A.
Polish Journal of Chemistry
|
2003
|
Vol. 77 / nr 8
985-994
EN
Thermal stability of primary sugar allyltin derivatives: Sug-CH=CH-CH2SnBu3 was studied. These organometallics with a pyranose ring are stable up to at least 214°C (boiling trichlorobenzene), while those with a furanose ring undergo already at 180°C a controlled decomposition with elimination of the tributylstannyl moiety and opening of the five-membered ring. The mechanism of this process is discussed.
9
Content available remote Allilocynowe pochodne cukrów prostych w syntezie układów karbocyklicznych
Jarosz S., Skóra S., Szewczyk K.
Wiadomości Chemiczne
|
2002
|
[Z] 56, 7-8
661-678
EN
Sugar allylic alcohols of the general formula Sug-CH=CH-CH2OH are easily converted into the allyltin derivatives Sug-CH=CH-CH2SnBu3 (7) by conversion into xanthate followed by its thermal rearrangement and subsequent SR2' reaction of resulting thiocarbonate with tri-n-butyltin hydride. Allyltin derivatives 7 undergo a controlled rearrangement with zinc chloride to dienoaldehydes CH2=CH-CH=CH-CH(OR)3CHO with the trans geometry across the internal double bond (3-E). Dienoaldehydes 3-E react with the C2-Wittig-type reagents [phosphoranes: Ph3P=CH-COR or phosphonates: (MeO)2P(O)CH2COR] to afford trienes 18 [CH2=CH-CH=CH-CH(OR)3CH=CH-C(O)-R), which undergo the intramolecular Diels-Alder reaction to give optically pure highly oxygenated bicyclo[4.3.0]indene derivatives 5 with the trans junction between the five and six-membered rings. Alternatively, the dienoaldehyde 3-E can be converted into - regioisomeric to 18 - triene 24 [CH2=CH-CH=CH-CH(OR)3C(O)-CH=CH-R], cyclization of which furnish optically pure bicyclo[4.4.0]decane derivatives 4 with the cis junction between both six-membered rings. On the other hand, sugar allylic bromides react with with tri-n-butyltin cuprate to afford a mixture of the primary and secondary allyltin derivatives [Sug-CH=CH-CH2SnBu3 (7) and [Sug-CH(SnBu3)-CH=CH2] (15) respectively]. Both isomers 7 and 15 might be converted into the trans dienoaldehyde 3-E by action of ZnCl2. However, thermal behavior of these regioisomers is different. The primary derivative 7 is stable up to at least 170 °C, while the secondary one (15) undergoes elimination of the tributylstannyl moiety already at 140 °C (boiling xylene) to afford dienoaldehyde with the cis-geometry across the internal double bond (3-Z). Such aldehyde was used for the preparation of - isomeric to 5 - derivative of bicyclo[4.3.0]indene with the cis-configuration between both rings (23). The stereochemistry of all these cyclizations might be rationalized assuming the endo-transition states of the intramolecular Diels-Alder reactions. Mechanism of the rearrangement of sugar allyltin derivatives 7 and 15 to unsaturated aldehydes 3-E and 3-Z is discussed.
10
Conduction Microcalorimetry and 13C NMR Spectroscopic studies on the Complexing Ability of D-erythro-L-manno-D-gluco-dodecitol with Selected Lanthanide Salts in Water Solutions
Mach M., Utzig E., Jarosz S.
Polish Journal of Chemistry
|
2002
|
Vol. 76 / nr 4
565-574
EN
Complexing ability of D-erythro-L-manno-D-gluco-dodecitol (1) with lanthanides salts: La(NO3)3ź6H2O and PrCl3ź6H2O in water by conduction microcalorimetry and 13C NMR spectroscopy was studied. It was compared to the complexing ability of known D-galactitol (2), D-mannitol (3), and D-glucitol (4) under the same conditions.
11
Coupling of the C6 and C6' Positions of Sucrose by Metathesis Reaction
Jarosz S., Listkowski A., Mach M.
Polish Journal of Chemistry
|
2001
|
Vol. 75, nr 5
683-687
EN
1_,2,3,3_,4,4_-Hexa-O-benzylsucrose (7) was converted into diallyl ether 11 and subjected to metathesis reaction with the Grubbs' catalyst. The expected macrocyclic product (12) was obtained in a good yield as a cis/trans mixture of olefins, hydrogenation of which gave fully deprotected saturated compound 13.
12
Allylation of Sugar Diols Under Phase Transfer Conditions Using Potassium Carbonate as a Base
Jarosz S., Szewczyk K.
Polish Journal of Chemistry
|
2000
|
Vol. 74, nr 8
1115-1122
EN
Allylation of sugar vic-diols (with a primary and secondary OH groups) under the phase transfer conditions (allyl bromide, K2CO3, 18-crown-6, toluene) afforded a mixture of both monosubstituted allyl ethers and small amounts of the di-allyl derivative. Interestingly, the cyclic carbonate was also isolated from the post reaction mixture. Its formation may be explained by reaction of the di-allyl carbonate, formed in situ under the reaction conditions, with the 1,2-diol.
13
Synthesis of sucrose derivatives modified at the terminal carbon atoms
Jarosz S., Mach M.
Polish Journal of Chemistry
|
1999
|
vol. 73 nr 6
981-988
EN
The methodology for the preparation of various derivatives of sucrose modified at C1', C6, and C6'-positions is presented. 6-Amino-, 6'-amino, and 6,6'-diamino-penta-O-benzylsucroses (16,17 and 18 respectively), as well as appropriate uronic acids (characterized as methyl esters: 19-22), have been obtained from 2,3,4,3',4',-penta-O-benzylsucrose (1). The usefulness of this approach was exemplified by the preparation of 1'-O-benzyloxymethyl-6-deoxy-6-C-(2-furyl)-2,3,4,3',4'-penta-O-benzylsucrose (26).
14
Simple Synthesis of D-erythro- and L-erythro-D-gluco-octoses
Jarosz S., Skóra S., Kościołowska I.
Polish Journal of Chemistry
|
1999
|
Vol. 73, nr 11
1797-1802
15
Synthesis and Application of allyltin derivatives in organic chemistry
Jarosz S., Kozłowska E.
Polish Journal of Chemistry
|
1998
|
Vol. 72, nr 5
815-831
EN
Methods of the preparation of allyltin derivatives are reviewed. Application of these compounds in stereocontrolled organic synthesis is presented.
16
Reactivity and crystal structure of 1,2:3,4:5,6-Tri-O-isopropylidene-D-gluconolactone
Jarosz S., Ciunik Z.
Polish Journal of Chemistry
|
1998
|
Vol. 72, nr 7
1182-1190
EN
1,2:3,4,5,6-Tri-O-isopropylidene-D-gluconate (1) undergoes the beta-elimination reaction in the presence of LDA to afford 3-deoxy-1,2:5,6-di-O-isopropylidene-D-erythro-hex-3-enolactone (6). Attempts to prepare the phosphonate 4 by reaction of 1 with dimethyl methylphosphonate in the presence of LDA failed; only elimination product 6 was isolated from the reaction mixture. The sugar phosphonate 8 (protected form of 4) was prepared from methyl 2-O-benzyl-3,4:5,6-di-O-isopropylidene gluconate (7) by reaction with (-)CH2P(O)(OMe)2. The crystal structure of 1 is reported.
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