Summary:
The subject of the present diploma thesis is the phytochemical study of four
tropical Cordia species from Panama, Cordia alliodora (Ruiz & Pav.) Oken,
Cordia colloccoca L., Cordia megalantha S.F. Blake and Cordia panamensis Riley,
in order to isolate and determine the chemical structure of their chemical
constituents.
The genus Cordia is a prolific source of structurally diverse secondary
metabolites with a broad range of biological activities. The introduction of
this thesis focuses on a literature review of the natural products that have
been isolated and identified from other species of the genus, as well as the
uses in traditional medicine and the biological activities of members of this
genus.
The methanolic extract of C. alliodora root bark, the dichloromethane and
methanolic extracts of C. colloccoca leaves and the dichloromethane extracts of
leaves of C. megalantha and C. panamensis were subjected to various
chromatographic separations to afford 22 secondary metabolites. In the
experimental part of this study, the extraction and isolation procedures and
the structural elucidation of the isolated compounds by means of 1D 1H-/13C-NMR
and 2D NMR spectra, assisted also by HRESI-MS, are described.
The following chemical constituents were isolated and structurally determined:
allantoin (1), rosmarinic acid (2), canthoside C (3), N-carbamoylputrescine (in
the form of its acetate salt) (4), 5-O-[β-D-apiofuranosyl-(1>6)-β-
D-glucopyranosyl]phthalide (5) and
N-(2E)-3-[(2S,3R)-2-(4-hydroxy-3-methoxyphenyl)-3-
(hydroxymethyl)-7-methoxy-2,3-dihydro-1-benzofuran-5-yl]acryloylglycine (6) were
isolated from C. alliodora. Among them 5-O-[β-D-apiofuranosyl-(1>6)-β-
Dglucopyranosyl]phthalide (5) and
N-(2E)-3-[(2S,3R)-2-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-7-methoxy-2,3-
dihydro-1-benzofuran-5-yl]acryloylglycine (6)
are new natural products, while N-carbamoylputrescine and canthoside C are novel
within Cordia genus and the whole Boraginaceae family. The dichloromethane
extract of C. panamensis yielded lupenone (7), lupeol (8), β-amyrin (9), β-
sitosterol (10) and stigmast-4-en-3-one (11). Lupenone and stigmast-4-en-3-one
are reported for the first time within the Cordia genus. Lupenone, lupeol, β-
sitosterol and stigmast-4-en-3-one were also isolated from the dichlomethane
extracts of C. colloccoca (13-16) and C. megalantha (17-20). Moreover, the
methanolic extract of C. colloccoca afforded the
two flavonoids afzelin (21) and quercitrin (22).
Furthermore, the total phenolic content of the methanolic extracts of the four
plants was determined according to the Folin-Ciocalteau method. The results
showed that all species contain a considerable amount of phenols, but the
highest content of total phenolic compounts was detected in the C. alliodora
root bark extract.
Keywords:
Genus Cordia L., New phthalide glycoside, New lignanamide, Total phenolic content, Folin-Ciocalteau method
