0000000000140364
AUTHOR
Pietro Venturella
Eubotriol and eubol, new diterpenes fromSideritis euboea
2 new diterpenes Eubotriol (ent-kaur-16-ene-7α, 15β, 18triol) (I), and eubol (ent-kaur-16-ene-7α-acetoxy-15β, 18 diol) (II) have been isolated from Sideritis euboea Helder.
Ucriol, an epoxy-diterpene from Sideritis syriaca
Abstract The isolation of a new epoxy-diterpene from the inflorescence of Sideritis syriaca (S. sicula Ucria) is described. Its structure and stereochemistry were established by spectroscopy and partial synthesis.
A diterpene, distanol, from Sideritis distans
Abstract A new diterpene, distanol, has been isolated from the petrol extract of the aerial part of Sideritis distans Wild. Its structure stereochemistry has been assigned by spectroscopic methods.
Coumarins from Seseli bocconi
Abstract A new khellactone, bocconin, in addition to known compounds, have been isolated from Seseli bocconi subsp. bocconi and subsp. praecox Gamisans . Their structures were elucidated on the basis of spectral analyses and hydrolytic studies.
Phytochemical Investigation of the Labiate Dorystoechas hastata
Abstract Carnosol (11,12-dihydroxyabieta-8,11,13-trien-20-oic acid 20,7-lactone), and rosmanol (7α, 11, 12-trihydroxy-abieta-8, 11, 13-trien-20 oic acid-20, 6-lactone), two abietane diterpenes previously isolated from Rosmarinus officinalis, have been isolated from leaves of Dorystoechas hastata. Luteolin, luteolin-7-glucoside, 6-methoxyluteolin-7-glucoside, caffeic acid and chlorogenic acid have also obtained from the same source. The co-occurrence of carnosol, rosmanol and 6-methoxyluteolin-7-glucoside support the close relationship of these two genera.
Revised structure for siderin
New diterpenes from Sideritis sicula
Abstract Two new diterpenes have been isolated from Sideritis sicula : sideripol, ent -18-acetoxy-7α-hydroxykaur-15-ene and epoxysideritriol, ent -15β,16β-epoxykauran-7α,17,18-triol. The previously known diterpene eubol, ent -7α-acetoxykaur-16-en-15β,18 diol has also been obtained from the same source.
On the reactions between ethyl benzoylacetate and anisidines
4-Hydroxy-7-methoxy-3-[(m-methoxyphenylimino)-phenylmethyl]-2-quinolone (6) was a by-product of the condensation of ethyl benzoylacetate and m-anisidine; no corresponding products were obtained from p- and o-anisidine. From o-anisidine, 2-phenyl-8-methoxy-4-quinolone (1c) was isolated and characterized; the same reaction also gave 2-phenyl-4-o-anisidyl-1-8-methoxy-quinoline (11) and the Schiff base (14) as by-products; the crotonamide (15) also isolated, is a possible intermediate of the cyclization. The direct condensation of anisidines with ethyl benzoylacetate in diphenyl ether and the transformations of some intermediates were studied.