StatusThe thesis was presented on the 8 November, 2007
Approved by NCAA on the 20 December, 2007
Abstract– 0.38 Mb / in romanian
1.02 Mb /
The dissertation is devoted to the elaboration of new and efficient methods for directed and stereoselective synthesis of biologic active polyfuncţional drimanic sesquiterpenoids. Starting from accesibile labdane diterpenoids larixol, sclareol and their norlabdane derivatives, using as key step photolytic degradation by Norrish II reaction were obtained drimanic dienes: 6a-acetoxy-drim-8(12),9(11)-diene, drim-8(12),9(11)-dien-6-one, drim-7,9(11)-dien-6-one and drim-7,9(11)-diene, convenient syntones for synthesis of polyfunctional drimanic derivatives and highly terpenoids.
From photolytic reaction products were izolated and identified, by X-ray diffraction including, the secondary norlabdanic compounds with unusual bi- and tricyclic structure: 6a-acetoxy-9,13b-epoxy-13b-methylpodocarpane, (1S,3S,6R,7R,9S,10R)-3,6,7,11,11-pentametyl-2-oxa-tetracyclo-[8.4.0.01,6.03,7]-tetradec-9-yl аcetate, 6a-acetoxy-8b,13β;13α,17-diepoxy-14,15-bisnor-labdane, ciclobuto-(18→6)-14,15-bisnorlabd-8(17)-en-6-ol-13-one and 2,4-dinitrofenyl-hidrazones obtained from the last compound.
Were realized new, short and efficient synthesis of natural and biologic active compounds: (+)-drim-9(11)-еn-8a-ol, (-)-albrassitriol, (-)-epi-albrassitriol, fragrolide, 6a-acetoxyeurifurane, 6a-hydroxyeurifurane, 6-cetoeurifurane and prouved the utility of photooxidative dehydrogenation reaction of drimanic and homodrimanic compounds with „8-en-7-on” structural unite for preparation of a,a¢-dienones: methyl ester of 11-homodrim-5,8-dien-7-on-12-oic acid and 11,12-diacetoxydrim-5,8-dien-7-one.
In base of drim-7,9(11)-diene were selectively synthesised polyhidroxylated compounds: drim-7-en-9α,11-diol, drim-9(11)-en-7α,8α-diol, drim-7α,8α,9α,11-tetraol şi drim-7β,8β,9α,11-tetraol, which can serve as intermediates for synthesis of biologic active labdane diterpenoids.
Under consideration  :