Dimitar Peev

Iridoid glucosides from three Veronica species

Abstract A new iridoid glucoside, 6′-O-menthiafoloylmussaenosidic acid, was isolated from the methanolic extract of Veronica bellidioides along with 11 known iridoid glucosides and the aromatic glucosides, picein and 4-O-glucopyranosylzingeron. The structure of the new iridoid was elucidated on the basis of its spectral data. Geniposidic acid and 4-O-glucopyranosylzingeron were found for the first time in the genus Veronica and verminoside in V. bellidioides. Nine known iridoids of which the major ones were mussaenoside and aucubin were found in V. alpina, and nine known iridoids with amphicoside as the major one were found V. kellererii.

Iridoid glucosides of the genus Veronica s.l. and their systematic significance

Abstract. 16 iridoid glucosides and 3 aromatic compounds were isolated from Bulgarian natural populations of Veronica L. and Pseudolysimachion Opiz species. The distribution of 11 compounds in 34 species (96 samples) was shown. Seven Veronica and Pseudolysimachion species were screened for iridoids for the first time and a phenylethanoid glycoside, calceolarioside C, was found for the first time in the genus Veronica. The systematic significance of iridoid glucosides at subspecies, species, sectional, and generic levels is discussed. A correlation between the chemical characters (iridoids and flavonoids) and the chromosome base numbers of the perennial Veronica species was established. Origin of the annual species from the perennials through two evolutionary lines was supposed.

Terpenoids from Achillea clypeolata

Abstract A new sesquiterpene alcohol named clypeotriol and characterised as eudesm-4(15)-en-3 α ,7 α , 11-triol was isolated from Achillea clypeolata collected in south-western Bulgaria. Populations of the same taxon growing in the eastern regions of Bulgaria afforded only sesquiterpene lactones two of which were the novel guaianolides 3 α ,4 α -epoxyrupicolin-A and 3 α ,4 α -epoxyrupicolin-B. The structures of the new compounds were elucidated on the basis of spectral data.

Different substitution tendencies of leaf flavones in theVeronica hederifolia group (Scrophulariaceae)

Flavonoid patterns of several provenances ofVeronica triloba, V. sublobata, andV. hederifolia s. str. have been investigated. 7-0-glucuronides of apigenin and luteolin as well as of 6-substituted (6-hydroxyluteolin and hispidulin) and 3′-methylated (chrysoeriol) derivatives represent characteristic accumulation tendencies in theV. hederifolia group. The three species show slightly different flavonoid profiles.V. hederifolia exhibits a cumulative pattern of all compounds occurring either inV. triloba orV. sublobata, thus supporting the hypothesis of an allopolyploid origin ofV. hederifolia.

DISTRIBUTION AND RECOURCE EVALUATION OF THE TRIBULUS TERRESTRIS L. - MALTESE CROSS (ZYGOPHYLLACEAE) IN POPULATIONS FROM SOUTH BULGARIA

ABSTRACT During the vegetation season june—September 2009 a investigation on the distribution and resource evaluation of the 55 Tribulus terrestris populations in South Bulgaria has been organized. They belongs to the 6 florobotanical regions of the country. As an element of the wild flora, and in the same time as a weed, that species inhabits abandoned places, vineyards, agricultural terrains, coastal and inland sands from 0 to 800 m.s.l.a. The populations developed on slightly humid, with good aeration soils, formed the most highest green mass yields in the limits of 5.25 kg to 89 tons. per dk. The total amount of the recourses from the investigated territory can be evaluated in the limits of some 615 tons fresh mass.

Florogeographical Elements and Evolutionary Trends in the Bulgarian Flora

The specific geographical location of Bulgaria, its geological history, and the varied relief underlie the contemporary richness of the Bulgarian flora. It includes 3700 species of vascular plants, among them 170 Bulgarian endemic species and 100 subspecies, and about 200 Balkan endemic species and subspecies. Analysis of the origin and the relationships between the various elements of Bulgarian flora demonstrates 92 types of florogeographical (floristic) elements. Nine Bulgarian mountain ranges and massifs may be ranked as follows according to the number of their endemic plant taxa: Stara Planina (90 species and subspecies), Rhodopes (over 80), Pirin (over 70), Rila (about 50), Vitosha (25), Strandja (19), Sredna Gora (12), Belasitsa (eight), and Osogovo (six). The complex nature of the Bulgarian flora, its high species diversity, and the relatively high percentage of endemism determine its high conservation value

Terpenoids from Achillea clusiana

Aerial parts of A chillea clusiana include two new chrysanthemol derivatives and three new guaianolides in addition to six known sesquiterpenoids. The structures of the new compounds were elucidated by spectroscopic methods.

Intraspecific Variability of Biologically Active Compounds of Different Populations of Tribulus Terrestris L. (Zygophyllaceae) in South Bulgaria

ABSTRACT The biologically active compounds protodioscin, prototribescin, dioscin and rutin were investigated in the samples originating from 25 natural populations distributed in South Bulgaria, including four floristic regions. The samples were collected along the ecological cline - “type of soil—degree of humidity” and analyzed by an HPLC method. The variability of the investigated compounds was evaluated and cluster analysis results were interpreted in order to discover intraspecific variability and eventual correlation with some ecological conditions.