Sintetičke studije analoga paklitaksela sa modifikovanim D-prstenom

A synthetic sequence has been developed for the preparation of 9,10-di-O-diacetyl-4-desmethylene-4 beta-(3-butenyl)-4 alpha-hydroxy-5-O-mesyltaxicin I-1,2-carbonate 3, an intermediate in an attempted synthesis of a cyclobutane paclitaxel analogue. A series of reactions of 3 were investigated, including the protection of the sterically hindered C-4 alpha-hydroxy group and the oxidative cleavage of the terminal double bond. Cyclization of 13 to the cyclobutane-containing intermediate failed due to the unexpected instability of the dimethylsilane protecting group under basic conditions.Razvijena je sintetička sekvenca za dobijanje 9,10-di-O-acetil-4-desmetilen-4β-(3-butenil)-4α-hidroksi-5-O-meziltaksicin I-1,2-karbonata (3), intermedijera u pokušanoj sintezi ciklobutanskog analoga paklitaksela. Ispitivana je mogućnost dalje hemijske transformacije jedinjenja 3, kao što je zaštita sterno izrazito zaštićene C-4α hidroksilne grupe i oksidativna fragmentacija terminalne dvostruke veze. Ciklizacija jedinjenja 13 nije dala željeni rezultat - intermedijer sa ciklobutanovim prstenom, što je posledica neočekivane nestabilnosti DMS-zaštitne grupe u baznim reakcionim uslovima

Semisynthesis of Taxol (R): an improved procedure far the isolation of 10-deacetylbaccatin III

From the needles of domestic yew, (Taxus baccata), 10-deacetylbaccatin III (10-DAB) call be isolated in quantities of up to 297 mg per kg of fresh needles. Additional quantities of 10-DAB call be obtained from the extract by NaBH4 mediated reductive hydrolysis of baccatin esters. A four-step procedure converts 10-DAB into taxol in 58% overall yield

Supplementary data for the article: Vulovic, B.; Trmcic, M.; Matovic, R.; Saicic, R. N. Cyclization Reactions of Oxyallyl Cation. A Method for Cyclopentane Ring Formation. Organic Letters 2019, 21 (23), 9618–9621. https://doi.org/10.1021/acs.orglett.9b03791

Supplementary material for: [ https://doi.org/10.1021/acs.orglett.9b03791]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3819

Supplementary data for the article: Vulovic, B.; Trmcic, M.; Matovic, R.; Saicic, R. N. Cyclization Reactions of Oxyallyl Cation. A Method for Cyclopentane Ring Formation. Organic Letters 2019, 21 (23), 9618–9621. https://doi.org/10.1021/acs.orglett.9b03791

Supplementary material for: [ https://doi.org/10.1021/acs.orglett.9b03791]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3819

Model studija u sintezi epotilona - alternativni pristup sintezi C1-C7 fragmenta

In this model study an alternative synthetic approach to the C1-C7 fragment of epothilones was investigated. Starting froth 4,4-dimethylcyclopentenone, a 7 step reaction sequence afforded the key intermediate 7 in 27%, overall yield. Surprisingly, the attempted deprotection of latent functionalities in 7 failed, indicating the incompatibility of the ethoxyethyl protective group with the reaction conditions employed.U okviru model studije ispitivan je alternativni sintetički pristup C1–C7 fragmentu molekula epotilona. Polazeći od 4,4-dimetilciklopentenona, ključni intermedijer 7 dobijen je u sedam faza, u ukupnom prinosu od 27 %. Deprotekciju latentnih funkcionalnih grupa u molekulu 7 nije bilo moguće izvršiti, zbog iznenađujuće labilnosti etoksietil zaštitne grupe u baznim reakcionim uslovima

Supplementary data for the article: Vulović, B.; Marić, I.; Matović, R.; Saicíć, R. N. Synthesis of Vinyldihydropyran by Cooperative Catalysis. Journal of the Serbian Chemical Society 2016, 81 (12), 1335–1343. https://doi.org/10.2298/JSC161102103V

Supplementary material for: [https://doi.org/10.2298/JSC161102103V]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2388

Supplementary data for article: Bihelović, F.; Karadžić, I.; Matović, R.; Saičić, R. Total Synthesis and Biological Evaluation of (-)-Atrop-Abyssomicin C. Organic and Biomolecular Chemistry 2013, 11 (33), 5413–5424. https://doi.org/10.1039/c3ob40692j

Supplementary material for: [https://doi.org/10.1039/c3ob40692j]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1388

Supplementary data for article: Marjanović-Trajković, J.; Divjakovic, V.; Matovic, R.; Ferjančić, Z.; Saičić, R. Double Asymmetric Induction in Organocatalyzed Aldol Reactions: Total Synthesis of (+)-2-Epi-Hyacinthacine A(2) and (-)-3-Epi-Hyacinthacine A(1). European Journal of Organic Chemistry 2013, 2013 (25), 5555–5560. https://doi.org/10.1002/ejoc.201300716

Supporting information for: [https://doi.org/10.1002/ejoc.201300716]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1389

Stereoselektivne sinteze α-hidroksi-β-aminokiselina iz prirodnih hiralnih prekursora

A method for the stereoselective homologation of -amino acids into syn-α-hydroxy-β-amino acids is described, based on the conversion of stereoisomeric cyanohydrins into trans-oxazolines. The synthetic potential of the method is illustrated in the enantioselective formal synthesis of Bestatin.Opisana je metoda za stereoselektivnu sintezu α-hidroksi-β-aminokiselina syn-konfiguracije, polazeći od α-aminokiselina, kao prirodnih hiralnih prekursora. Enantioselektivnost procesa zavisi od strukture polazne aminokiseline, kao i reakcionih uslova. Primena ove metode ilustrovana je u sintezi (2S,3R)-3-amino-2-hidroksi-4-fenilbutanske kiseline, konstituenta nekoliko važnih biološki aktivnih jedinjenja

Intramolekulska Barbier-ova reakcija u vodi - sinteza petočlanih i šestočlanih prstenova

Zinc or indium promoted intramolecular Barbier reactions of aldehydes containing a suitably positioned allylic or propargylic halide unit afford unsaturated cyclic alcohols in moderate yields.Aldehidi koji u pogodnom položaju poseduju alil-halogenidnu ili propargil halogenidnu strukturnu jedinicu reaguju u vodenim uslovima sa cinkom ili indijumom, pri čemu nastaju nezasićeni ciklični alkoholi u umerenim prinosima