On the Occurrence of D-Glycero-D-Manno-Heptose in Lipopolysaccharides

by O. Holst

Research Center Borstel, Center for Medicine and Biosciences, 23845 Borstel, Germany

(Received January 4th, 1999)

Lipopolysaccharides (LPS) consist of three regions, i.e. the lipid A, the core region, and the O-specific polysaccharide. The core region and the lipid A represent a common structural unit occurring in all LPS. The structures of the core region of various bacteria have been investigated intensively for the past ten years, and several core regions containing D-glycero-D-manno-heptose which is the biosynthetic precursor of the common core constituent L-glycero-D-manno-heptose have been identified. In this review, these core structures are summarized and briefly discussed.

Preparation of Esters, Ethers and Acetals
from Unprotected Sucrose

by G. Descotes, J. Gagnaire, A. Bouchu, S. Thévenet, N. Giry-Panaud,
P. Salanski, S. Belniak, A. Wernicke, S. Porwanski and Y. Queneau

Unité Mixte de Sucrochimie CNRS – Béghin-Say (UMR 143), c/o Eridania Béghin-Say, 27 Bd du 11 Novembre 1918, B.P. 2132, 69603 Villeurbanne Cedex, France

(Received January 12th, 1999; revised manuscript March 9th, 1999)

The direct transformation of unprotected sucrose in the context of the preparation of derivatives of industrial interest is a challenging task. We show how the intrinsic properties of sucrose, i.e. its electronic, conformational and structural characteristics, provide to the chemist some sources of reactivity and selectivity. We report our recent results in the synthesis of sucrose esters, carbonates and ethers in aqueous medium, as well as some work on the reaction of sucrose in organic solutions to make acetals involving either the [OH-4;OH-6] or the [OH-2;OH-3] diol systems.

From Carbonyl Cyanide
to N-Glyoxyloyl-(2R)-bornane-10,2-sultam

by M. Achmatowicz¹ and J. Jurczak^1,2

¹Institute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
²Department of Chemistry, Warsaw University, 02-093 Warsaw, Poland

(Received February 5th, 1999; revised manuscript March 16th, 1999)

Basic chemical properties of activated carbonyl compounds, such as carbonyl cyanide, dialkyl mesoxalates and alkyl glyoxylates are reviewed. Their applications to important synthetic problems are also described. Special attention is given to glyoxylates of chiral alcohols and N-glyoxyloyl-(2R)-bornane-10,2-sultam.

Various Amino Protecting Groups Influence on ¹H and ¹³C Chemical Shifts in a 2-Deoxy-2-amino Glucopyranoside

by L. Olsson, Z.J. Jia and B. Fraser-Reid

Natural Products and Glycotechnology Research Institute Inc.,
4118 Swarthmore Rd, Durham, North Carolina 27707, USA

(Received January 14th, 1999)

One glycoside, pent-4-enyl 2-amino-3,4-di-O-benzoyl-6-O-t-butyldimethylsilyl-2-deoxy-b-D-glucopyranoside (1), has been derivatized at the amino function into five related compounds: ammonium trifluoroacetate, N-acetyl, tetrachlorophthalimide, phthalimide and azide. The ¹H and ¹³C NMR spectra of these compounds have been fully assigned and compared. Significant influence on the chemical shifts given by the amino functionality can be found in the pyranosidic ring at position 1, 2 and 3. Only minor variations were found throughout the remaining positions.

a,b-Unsaturated Sugar d-Lactones;
Preparation and Conjugate Addition
of Hydroxylamines and Hydrazines

by I. Panfil, D. Mostowicz and M. Chmielewski

Institute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland

(Received January 25th, 1999)

Oxidation of 2,3-unsaturated glycosides with hydrogen peroxide in the presence of molybdenum trioxide as catalyst provides corresponding a,b-unsaturated sugar d-lactones via the anomeric hydroperoxide stage. Conjugate addition of N-substituted hydroxylamines and hydrazines to these d-enealdonolactones proceeds anti to the C-6 carbon atom. The adducts undergo rearrangement consisting in opening of the lactone ring and formation of 3-substituted isoxazolidin-5-one or 5-substituted pyrazolidin-3-one, respectively. Introduction of a leaving group to the polyol side chain of both heterocycles induces further rearrangements.

Synthesis of Modified Oligosaccharide
Derivatives by Ferrier Rearrangement

by E. Wieczorek and J. Thiem

Institut für Organische Chemie, Universität Hamburg,
Martin-Luther-King-Platz 6, D-20146 Hamburg, Germany

(Received January 30th, 1999)

Various glycals of the hexose and pentose series and different dideoxy hexopyranosides undergo smooth (Lewis) acid-catalyzed allylic rearrangement reactions to regioisomeric deoxygenated disaccharide derivatives. The corresponding saturated components were obtained by hydrogenation. In addition, the neutral version of the Ferrier reaction employing pentenoyl glucal was tested, which gave rearrangement and addition products. Finally, certain glycals were condensed with differently functionalized glycals as aglyconic components to form disaccharide glycals.

Synthesis of Two Hyaluronic-Acid-Related Oligosaccharide 4-Methoxyphenyl Glycosides Having
a b-D-Glucuronic Acid Residue at the Reducing End

by K.M. Halkes¹, T.M. Slaghek², T.K. Hyppönen¹, J.P. Kamerling^1,
and J.F.G. Vliegenthart¹

¹Bijvoet Center, Department of Bio-Organic Chemistry, Utrecht University,
P.O. Box 80.075, NL-3508 TB Utrecht, The Netherlands
²Agrotechnological Research Institute (ATO-DLO), P.O. Box 17,
NL-6700 AA Wageningen, The Netherlands

(Received February 18th, 1999)

Synthesis of two hyaluronic-acid-related oligosaccharides, the 4-methoxyphenyl b-glycosides of b-D-GlcpA-(1Ž3)-b-D-GlcpNAc-(1Ž4)-D-GlcpA and b-D-GlcpA-(1Ž3)-b-D-GlcpNAc-(1Ž4)-b-D-GlcpA-(1Ž3)-b-D-GlcpNAc-(1Ž4)-D-GlcpA, is described. D-Glucopyranosyluronic acid residues were obtained by selective oxidation at C6 of corresponding D-glucopyranosyl residues after construction of the oligosaccharide backbones, using pyridinium dichromate and acetic anhydride.

pp. 1133-1141

Total Synthesis of Both Enantiomers of Daunosamine
and Ristosamine

by B. Szechner, O. Achmatowicz and K. Badowska-Rosłonek

Pharmaceutical Research Institute, Rydygiera Str.8, 01-793 Warszawa, Poland

(Received December 17th, 1998; revised manuscript February 23rd, 1999)

Efficient, enantioselective syntheses of the title 3-amino-2,3,6-trideoxyhexoses from non-carbohydrate precursors, (S)- and (R)-1-(2-furyl)ethanol, readily available by enzyme-mediated kinetic resolution, are described. Furan compound (S)-3 was converted into methyl pyranosid-4-ulose 6. Reduction of the carbonyl group in 6 yielded alcohol 8a and inversion of configuration at C-4 in the latter furnished alcohol 10a. An intramolecular amino-mercuration of their trichloroacetimidates 11 and 18, followed by reduction and hydrolysis, afforded methyl a-L-daunosaminide (16) and methyl a-L-ristosaminide (19), respectively. Methyl a-D-daunosaminide and methyl a-D-ristosaminide were synthesized by the same route, starting from (R)-3a.

pp. 1143-1152

Synthesis of Kedarosamine, a Sugar Portion of the Chromoprotein Antibiotic Kedarcidine

by W. Priebe¹, P. Skibicki¹, N. Neamati¹ , O. Achmatowicz²,
G. Grynkiewicz² and B. Szechner²

¹The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, U.S.A.
²Pharmaceutical Research Institute, 01-793 Warszawa, Poland

(Received February 26th, 1999)

Synthesis of the sugar portion (kedarosamine) of a recently discovered chromoprotein antitumor antibiotic and spiroketal-macrolide A82548A is described. Kedarosamine was prepared from readily available methyl a-L-rhamnoside. This route can also be used to prepare different glycosyl donors and analogues of kedarosamine potentially useful in the synthesis of biologically important congeners. The effect of a C-4 dimethylamino group (versus amino or acetamido substituents) on the conformation of pyranoside ring is discussed.

pp. 1153-1161

Synthesis and Properties of Derivatives
of 2-Deoxy-2-hydroxyimino-D-arabino-
-hexopyranosyl-L-cysteine and -thiophenol

by B. Liberek, R. Frankowski and Z. Smiatacz

Faculty of Chemistry, University of Gdansk, 80-952 Gdansk, Poland

(Received January 20th, 1999; revised manuscript March 8th, 1999)

3,4,6-Tri-O-acetyl-2-deoxy-2-hydroxyimino-a- and -b-D-arabino-hexopyranosides of thiophenol (3–5) as well as the methyl ester of N-benzoyl-L-cysteine (6,7) have been synthesized by condensation of 3,4,6-tri-O-acetyl-2-deoxy-2-nitroso-a-D-glucopyranosyl chloride (1) with thiophenol and the L-cysteine derivative, respectively. The glycopyranosides of thiophenol were modified at C-2 and C-3 positions to afford thiophenol derivatives with 2-deoxy-2-hydroxyamino-a-D-glucopyranosyl (13,14), 3-azido-2,3-dideoxy-2-hydroxyimino-a-D-arabino- (8), b-D-arabino- (10), and a-D-ribo-hexopyranosyl (9) structures. The conformation of the sugar residue and configuration at the anomeric center and of the hydroxyimino group were established on the basis of the ¹H, ¹³C, ¹⁵N NMR (DQF-COSY, TOCSY, NOESY, ROESY, HSQC, HMBC and HMBCN) spectrometric techniques and polarimetric data.

pp. 1163-1170

Stereoselective Synthesis of 2-Deoxyglycosides by
Use of 2-Deoxypyranosyl Dithiocarbamates as Donors

by I. Wandzik and W. Szeja

Silesian Technical University, Department of Chemistry, ul. Krzywoustego 8, 44-100 Gliwice, Poland

(Received January 14th, 1999; revised manuscript March 9th, 1999)

Glycosides, derivatives of 2-deoxysugars can be conveniently prepared by treatment of glycosyl dithiocarbamates (glycosyl donors) with hydroxy compounds (glycosyl acceptors) in the presence of thiophilic compounds as activators.

pp. 1171-1176

3,3'-Bis(4-substituted-quinolinyl) Disulfides

by K. Marciniec, T. Banasiak and A. Maslankiewicz

Department of Organic Chemistry, Silesian School of Medicine,
Jagiellonska 4, 41-200 Sosnowiec, Poland

(Received December 18th, 1998; revised manuscript February 15th, 1999)

Reaction of 4-alkoxy-, 4-alkylthio- and 1-methyl-4-oxo-1,4-dihydro-3'-alkylthio-3,4'-
diquinolinyl sulfides 2, 3 or 10 with sodium or potassium methoxides led to 4-alkoxy-3-(alkylthio)quinolines 5 and 4-alkoxy- or 4-alkylthio-3-quinolinethiolates 4 or 7 respectively, or thiolate 11. Thiolates 4, 7 and 11 were oxidized to 3,3'-bis(4-substituted-quinolinyl) disulfides 6, 8 and 12 respectively with 30% hydrogen peroxide or potassium ferricyanide solution. 4,4c-Dialkoxy derivatives 6a and 6b were hydrolyzed with boiling 18% hydrochloric acid to bis-quinolinone 13.

pp. 1177-1183

Synthesis Based on 9-Amino-N-picrylcarbazyl

by G. Ionita¹, M.T. Caproiu² A. Meghea³, O. Maior⁴,
M. Rovinaru⁴ and P. Ionita⁵

¹University of Pitesti, Dept. of Physical Chemistry, Gh. Doja 41, 0300 Pitesti, Romania
²Institute of Organic Chemistry, NMR Department, Spl. Independentei 202B, Bucharest 15 PO Box 258, Romania
³University "Politechnica" of Bucharest, Department of Applied Physical-Chemistry and Electrochemistry,
1 Polizu, Bucharest, Romania
⁴University of Bucharest, Dept. of Organic Chemistry, Soseaua Panduri 90-92, Bucharest, Romania
⁵Institute of Physical Chemistry, Spl. Independentei 202, 77208 Bucharest, Romania;
E-Mail: pionita@chimfiz.icf.ro

(Received October 14th, 1998; revised manuscript February 26th, 1999)

Starting from 9-amino-N-picrylcarbazole, the nitro-, cyano-, bromo- and dibromo-derivatives of the title compound, and the corresponding free radicals, were synthesized. The pK_a values and the redox properties of the compounds synthesized were reported.

pp. 1185-1189

The Synthesis of Organic Peresters
via the Phase Transfer Catalysis

by S. Baj and A. Chrobok

Institute of Organic Chemistry and Technology, Silesian Technical University,
Krzywoustego 4 st., 44-100 Gliwice, Poland

(Received December 18th, 1998; revised manuscript March 1st, 1999)

The acylation of alkyl hydroperoxides with acid chlorides under the phase transfer conditions (PTC) is studied. An evident catalytic effect was observed. This reaction can be considered as a convenient method for the synthesis of organic peresters.

pp. 1191-1202

Novel a-Hydroxyphosphonates – Enol Phosphates
Rearrangement

by A.E. Wróblewski and W. Karolczak

Institute of Chemistry, Faculty of Pharmacy, Medical University of LódŸ,
90-151 LódŸ, Muszyńskiego 1, Poland

(Received February 1st, 1999; revised manuscript March 15th, 1999)

CsF was found to be a very efficient basic catalyst for the rearrangement of a-hydroxy-b,g-epoxy(aziridino)phosphonates to enol phosphates. DBU and potassium fluorides (anhydrous or dihydrate) appeared less active in promoting this rearrangement, but strong enough to execute the retro-Abramov reaction. Because of the competition from the retro-Abramov reaction, stereochemistry of the rearrangement cannot be unequivocally assigned, but it seems reasonable that intermediates having the dimethoxyphosphoryl group and O-epoxide or N-aziridine atoms as leaving groups in the antiperiplanar positions are involved.

Studies on Condensed Heterocyclic Compounds. XX. Synthesis and Antibacterial Activity of Novel 6-Aryl-3-(1-p-chlorophenyl-5-methyl-1,2,3-triazol-4-yl)-s-triazolo[3,4-b]-1,3,4-thiadiazoles

by X.W. Sun¹, C.H. Chu¹, Z.Y. Zhang^1, Q. Wang² and S.F. Wang^2
1Department of Chemistry, National Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
²Department of Biology, Lanzhou University, Lanzhou 730000, P.R. China

(Received November 3rd, 1998; revised manuscript March 17th, 1999)

A series of novel 6-aryl-3-(1-p-chlorophenyl-5-methyl-1,2,3-triazol-4-yl)-s-triazolo[3,4-b]-1,3,4-thiadiazoles 6a–m have been synthesized in 49–64% yields by the cyclocondensation of 4-amino-3-(1-p-chlorophenyl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazole 5 with various aromatic acids in the presence of POCl₃. Biological activity of 6a–m was studied.

pp. 1209-1217

On the Julia Alkenylation Reaction in Vitamin D
Synthesis. Isolation of Four Geometrical Isomers
of Vitamin D₄

by P.R. Blakmore¹, P. Grzywacz², P.J. Kocienski¹, S. Marczak² and J. Wicha^2*

¹Chemistry Department, Glasgow University, Glasgow G12 8QQ, U.K.,
E-mail: P.Kocienski@chem.gla.ac.uk
²Institute of Organic Chemistry, Polish Academy of Sciences, POB 58, 01-224 Warsaw 42, Poland, E-mail: jwicha@ichf.edu.pl

(Received February 23rd, 1999; revised manuscript March 18th 1999)

Coupling of sulfone 2 and aldehyde 3b using the Julia alkenylation procedure has been reexamined using modern product separation techniques. It was found that vitamin D₄ 1b and its geometric isomers 10, 11 and 12 are formed in a ratio of 75:10:10:5, respectively. The building blocks 2 and 3b were prepared from vitamin D₂. Correlations for the structure assignment of vitamin D stereoisomers by ¹H NMR spectroscopy are presented.

pp. 1219-1225

Interception of a Thiocarbonyl Ylide by Thiouracil and Crystal Structure of the 2:1 Adduct

by G. Mlostoń¹, T. Gendek¹, A. Linden² and H. Heimgartner²

¹Department of Organic and Applied Chemistry, University of ŁódŸ,
Narutowicza 68, PL-90-136 ŁódŸ, Poland
²Organisch-chemisches Institut der Universität Zürich, Winterthurerstrasse 190,
CH-8057 Zürich, Switzerland

(Received December 28th, 1998; revised manuscript March 29th, 1999)

The reaction of thiocarbonyl ylide 1, generated in situ by thermolysis of the corresponding 2,5-dihydro-1,3,4-thiadiazole, with a twofold excess of thiouracil (4) yielded a mixture of the 1:2 adduct 5 and the 1:1 adduct 6 in a ratio of ca. 1:1. These interception products are formed by protonation of 1 and nucleophilic addition via the S- or O-atom. The structure of 5 has been established by X-ray crystallography.

pp. 1227-1231

Phase Equilibria in the Quasi-Binary Sections
AgGaS₂–GeSe₂ and AgGaS₂–AgGaGe₃Se₈

by I.D. Olekseyuk and M.V. Shevchuk

Department of Inorganic and Physical Chemistry, Volyn State University, Voli av.13, Lutsk 263009, Ukraine

(Received November 19th, 1998; revised manuscript February 16th, 1999)

pp. 1233-1235

Catalytic Hydrogen Transfer over Magnesia. XII.
Reduction of Metameric 1-Phenyl-x-butanones
(x = 1, 2 or 3) by 2-Propanol

by M. Glinski and P. Radomski

Faculty of Chemistry, Warsaw University of Technology, Laboratory of Catalytic Synthesis, Noakowskiego 3, 00-664 Warsaw, Poland. E-mail: marekg@ch.pw.edu.pl