Diterpenoids and cyclolanostanolides from Abies marocana

Stachyonic Acid: A Dengue Virus Inhibitor from Basilicum polystachyon

“…However, 2D NMR signals suggested a stereoisomer of 4 [tentatively assigned as stachyonic acid B ( 8 )] containing a Z ‐configured double bond at C12 (Figure ). This suspicion was confirmed when the chemical shifts, and coupling constants, of the diene protons for 14‐H and 15‐H (a and b) were compared and found to be a close match with the known labdane, labda‐7,12( Z ),14‐triene ( 9 ), which was isolated from Abies marocana …”

“…This suspicion was confirmedw hen the chemical shifts, and coupling constants, of the diene protons for 14-H and 15-H (a and b) were compared and found to be ac lose match with the known labdane, labda-7,12(Z),14-triene (9), which was isolated from Abies marocana. [20] However,f or optimum biological assay results pure material was required. Fortunately,argentation chromatography [that is, silver nitrate impregnatedu pon silica gel (SNIS)] [21] resolved this separation difficulty,a lthough derivatization was required.…”

“…[22] Firstly,t he 95:5 mixture of stachyonic acids Aa nd B was converted to the corresponding mixture of methyl esters (10), followed by SNIS chromatography to give pure methyl esters 11 and 12.M ethyl ester cleavage of 11 (and 12)p roved challenging, but eventually applying conditions reported by Waldvogel, involving cyanidea st he reagent, [23] afforded pure stachyonic acid A( 4), but not stachyonic acid B( 8)d ue to limited amountso fm aterial (Scheme 1). In terms of absolutes tereochemistry,g iven the sign of optical rotationf or stachyonic acid A( 4)( + 33.5), labdane 7 (+ 3.8) [19] and 9 (+ 19.8) [20] are the same, suggestst he configuration of positions 4, 9, and 10 are the same for stachyonic acid A. Attemptst og enerate ac rystalline derivate of 4,f or example, via the PTAD (13)c ycloadduct 14,f ailed (Scheme 1).…”

Spasmolytic effect of constituents from Lepechinia caulescens on rat uterus

“…9␤-Hydroxydehydroabietyl alcohol (4): Yellow oil; [α] 589 = +34 (c 0.002 CHCl 3 ); R f = 0.1, 4:1 hexanes-AcOEt; 1 H and 13 C NMR identical with literature values (Ohmoto et al, 1987;Barrero et al, 1992;Miguel del Corral et al, 1994).…”

Composition of the Essential Oil from the Seeds ofAbies marocana

“…It is known that endoperoxide diterpenoids (1), cyclolanostanolides (2,3), and sesquilignans (4) are amongst the components of the hexane and chloroform extracts from the needles and the wood of this tree. Nevertheless, the essential oil obtained from this species, which is used in Moroccan folk medicine to treat respiratory complaints (5), has not so far been studied.…”