The acetalization of phenyl 1-thio-α-L-arabinopyranoside with 2,3-butanedione in the medium of MeOH-CH(OMe) 3 -CSA proceeded with the prevailing formation of the corresponding 3,4-bisacetal that further was converted in compounds, which were regio-and stereoisomers of disaccharide block of OSW-1. O HO O SPh HO OH HO O SPh HO OAc I II IIIIn the sugar chemistry the necessity to work with awkward polyol systems makes the protective groups extremely important [1]. In the course of the planned synthesis of disaccharide block I for anticancer steroid OSW-1 based on the known components, glycosidedonor II and acceptor III [2, 3] (Scheme 1) we tested 2,3-butanedione in conditions described in [4] for the selective protection of the 3,4-diol moiety of triol II in the form of butane 2,3-bisacetal. The butane 2,3-bisacetal and the other similar protective groups introduced into the synthetic practice by Liu group [5] are known to provide a selective blocking in cycles of trans-vicinal diols, impart the products a crystalline structure, desired conformational rigidity, etc. [6].As seen from the structure of triol II all its hydroxy groups are located in the trans-equatorial reciprocal position, and here the possibility of the regiocontrolled acetalization depends mainly on the steric factors. In the experimental test of triol II acetalization by heating with excess 2,3-butanedione in the medium of MeOH-CH(OMe) 3 -camphorsulfonic acid (CSA) (catalyst) we obtained two expected acetals IV and V in the ratio ~3 : 1 and in the overall yield 80%. The main bisacetal IV is a crystalline substance easily isolated from compound V by chromatography on SiO 2 . Minor bisacetal V is oily substance containing ~10% of unidentifi ed isomeric compound. The assignment of the structure of regioisomeric acetals IV and V was carried out applying spectral data. Their 1 H NMR spectra contain a characteristic signal C 1 H which in the spectrum of 2,3-acetal V is located downfi eld (doublet, δ 4.77 ppm, J 9.6 Hz) with respect to the corresponding signal in the spectrum of compound IV (δ 4.47 ppm, d, J 9.35 Hz) because of the electron-withdrawing inductive effect of the closely Scheme 1.

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Mono-, bis-, tris-, tetrakis-, and hexakis-substituted cyclopropanation products of fullerene C 60 with diallyl malonate were synthesized according to Bingel-Hirsch. Except for the monocyclopropanation product, all other adducts were isolated as mixtures of regioisomers.II, n = 1; III, n = 2; IV, n = 3; V, n = 4. Functionalization of fullerenes is an important line in studies ensuring approaches to nanomaterials, supramolecular systems, medical agents, etc. [1][2][3][4][5]. A practical and popular synthetic approach to C 60 derivatives is that proposed by Bingel and Hirsch [6][7][8]; it is based on [1,2]-cycloaddition of malonates to double bond in C 60 in the presence of I 2 or CBr 4 and bases. As a result, the corresponding cyclopropanation products, methanofullerenes, can be obtained in moderate yield.With a view to obtain fullerene-containing monomers for radical polymerization and design of dendrimer structures with a fullerene base in the present work we synthesized allyloxycarbonyl-substituted methanofullerenes from C 60 and diallyl malonate (I) prepared by esterification of malonic acid with allyl alcohol.The reaction of fullerene C 60 with diallyl malonate (I) in the presence of CBr 4 and 1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU) at a ratio of 1 : 1.2 : 1.4 : 1.4 was carried out under conventional conditions [7] in toluene at room temperature in an inert atmosphere. By column chromatography on silica gel we isolated

The oxidation of (1S,5R,7R,S)-(4,7-dimethyl-6-oxabicyclo[3.2.1]oct-3-en-7-yl)methanol epimeric at the C 7 atom resulted in scalemic (5R)-5-acetyl-2-methylcyclohex-2-en-1-one.

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