ࡱ> 130E ujbjb .cculP ,: Z # -"#  .P P F F TEORIJSKO PROUAVANJE MEHANIZAMA MIGRACIJE ACILNE SKUPINE NA UGLJIKOHIDRATNOM PRSTENU THEORETICAL STUDY OF ACYL MIGRATIONS ON A CARBOHYDRATE RING Helena iak1, Marko Duki2 and Zlatko Mihali1 1Laboratory of Organic Chemistry, Faculty of Science, University of Zagreb, Strossmayerov trg 14, 10000 Zagreb, Croatia 2Laboratory of Supramolecular and Nucleozide Chemistry, Ruer Bokovi Institute, Bijenika cesta 54, 10000 Zagreb, Croatia Although there are many experimental observations of acyl group migration on carbohydrate rings,1,2 none of the molecular modelling attempts of their mechanism clarification did not give convincing results.3,4 The aim of this work is to explain the mechanism of O-2 ( O-3 trans acyl migration on a model compound (methyl-2-O-acetyl-(-D-xylopyranoside) using high level quantum-chemical calculations.  In solution there are several possible migration mechanisms, all of which presumably go through an ortho-acid, whose existence has been recently proved by the experiment.5 Gas phase mechanisms are different from those in the solution, and the individual solvent molecules have to be included in the calculations. [1] A. H. Haines, Adv.Carbohydr. Chem. Biochem. 33 (1976) 101-107. [2] R. W. Binkley. Modern Carbohydrate Chemistry, Marcel Dekker, Inc., New York, 1998, 143-144. [3] A. W. Nicholls, K. Akira, J. C. Lindon, R. D. Farrant, I. D. Wilson, J. Harding, D. A. Killick, J. K. Nicholson, Chem. Res. Toxicol. 9 (1996) 1414-1424. [4] T. Horrobin, C. H. Tran, D. Crout, J. Chem. Soc. Perkin. Trans. 1, 6 (1998) 1069-1080. [5] V. Petrovi, S. Tomi, M. Matanovi, Carbohydr. Res. 337 (2002) 863-867. &*BD^`z|  p    L M N ,Qadt謥ϝי6CJ5CJOJQJ jUmH CJOJQJ CJOJQJ ja6CJOJQJ jCJOJQJ6CJOJQJCJCJH*OJQJEHH*H* CJOJQJ5CJOJQJ5CJ5CJ<&(*"z r t v o $-d$]-a$ & p@ P !$a$ & p@ P !$0]0a$ & p@ P !$-]-a$ & p@ P !$-]-a$ & p@ P ! &(*"z r t v L M O P Q R S 0 (uv L M O P Q R S 0 (u$d$^`a$$d$a$tu CJOJQJ,/ =!"#/ $/ % |,, O @ w"{,, d'` nFػH_ảׇ6aPNG  IHDRrgAMAܲPLTEU~ pHYs.#.#x?vQIDATxͮܶ2-/py,oG#NЋ+]dU" /jEC.]X@.F?D~F$gC}:<9<5]<{j2b&`Li̸?]cLc&j.1I1M\cX>2"Үr[1B8,Bcel53*¾j-BM_\nU=|x[/ő|_&3{M@,c0s&k ,C7Ez0t.[k>ؙ 8s60DBupDV,&@r3#$|v>{./X-93ߓ9Egp>t/niP=1?aͻ` U̾s 13`Ml67LOEW*a*諊9wEG] 恮͙?C`3gUqfN(y ̔ NLUe؟̭sy"3ם`Fɺ*x'xd5J4s|?c4PҊwר8!י)z@Ѽu5y?(LMRBblզ 2E>"Ȁi7滅ijΌadF 39~Yd.LVe(R3tι -!;Fd(CT3"l "5[˕>EP "~0N1kE4T*Z}4@N1ᰫB,)>E;~+(iRjEh^0mE3h-ŮBSB+Hat4P)j!UkQ%J7dJf)Zu\`1 UAbfi3pVWʎzܪV1S^tnoxHYmdu+BE*Vs_D2֬,o̙i6!3~,j:T+M7JW6.$jl]AVg +&D49Ht:TZE{jwgn3eLkc/pz:iӆY_YsYjTH:WE]y8?ƃJ<0Q Ppm`ӄD䬇Ҏnqi 9*^oxfф1Uq&A~fwPt&Ac{Zu n4!g+;Cju.%D7jGuc+ӄlXT3瞉Q A^ :6h[li#L0Wnu0d̤\t7A".߆;fL݇Z]cvQrT^PN3TF#"[73:(#$Wօb1GG:OOXDU3~,\›#\sXK2GP.窏Pнf7 .A {F= $P!fH9K03n%t1gG%#9s$ p^#̣5ٱUM IS$2G;`IKǞk'e}zVg9G&{&w_&'gtOԄƘ}?r_VJVx'jB$'S~W1<㩓5dVL.ZM1$͸ Mcd|E|ߏi9rSR3k܄p'~,[j'sGҠ3yMhK3gozF`W=7'= =9 eK1gRBfc3Arۨ=?|.wa1cjNzf+`z`Wh$sfE]S}5=QeX9>y2=Bdc3ݓti{K Ṟ[N+IbZ/֟\YKA'[2T4H*:DBtݝЇU}5G6ƌGjD2Łg.%jbN=Y.|B쿋Ԭ|:sFK,:*t<5˘4# rpY*@J^wf!Joq~,*gf>º52v'Ȭ7٪B[fHەp߂,RTg:0*R}e? ]f0GIf'fH吣 ,G,9`q 8+lnY#M 1PpvdrzqWsD' .TXՠe3aC|M+VPd+ *seBs>Tśp̪@99/L"gpd3{b3Lj\ co 7|^Q!ǐ0٪ 1z,f f bN` s>o9^,~Z k+fǮ9̰Al 3'a~l30O,fxQ>as>.9K3ڊY>1gK| F:1t3o><,b~f5%̤y ,cq[cBtxθ܌Yb {(F]+̻U~.,E̴yJeDd~|;ߐ/us! rxb$A=1(ӝVb$ׇ6a@( &D*@J ~  C @A(:shema1_sazetak.tif"B S  ?Mu$ TO wOw:8iMac 3 Data Disk:dokumenti:Helena:Opatija:19_skup_Cicak28iMac 3 Data Disk:dokumenti:Helena:Opatija:19_skup_Cicak2BiMac 3 System Disk:Temporary Items:AutoRecovery save of 19_skup_Ci8iMac 3 Data Disk:dokumenti:Helena:Opatija:19_skup_Cicak28iMac 3 Data Disk:dokumenti:Helena:Opatija:19_skup_Cicak28iMac 3 Data Disk:dokumenti:Helena:Opatija:19_skup_Cicak28iMac 3 Data Disk:dokumenti:Helena:Opatija:19_skup_Cicak26iMac 3 System Disk:Temporary Items:Word Work File A_306iMac 3 System Disk:Temporary Items:Word Work File A_306iMac 3 System Disk:Temporary Items:Word Work File A_30Uw@(:(u   @GTimes New Roman5Symbol3 Arial3Times 1hk&sFsF A0d SO@UTEORIJSKO PROUAVANJE MEHANIZAMA MIGRACIJE ACILNE SKUPINE NA UGLJIKOHIDRATNOM PRSTENU Oh+'0 0 @L h t  'VTEORIJSKO PROUAVANJE MEHANIZAMA MIGRACIJE ACILNE SKUPINE NA UGLJIKOHIDRATNOM PRSTENUNEORKNormalKK20Microsoft Word 9.0J@Hʎ@\M@C@ds ՜.+,D՜.+,@ hp  "'_   VTEORIJSKO PROUAVANJE MEHANIZAMA MIGRACIJE ACILNE SKUPINE NA UGLJIKOHIDRATNOM PRSTENU Title 8@ _PID_HLINKS'A` :shema1_sazetak.tifI !"#$%&')*+,-./2Root Entry F"G41TableWordDocument.SummaryInformation( DocumentSummaryInformation8(CompObjX FMicrosoft Word DocumentNB6WWord.Document.8