Megaphone (molecule)
Encyclopedia
Megaphone is a cytotoxic
neolignan obtained from Aniba megaphylla
, a flowering plant
of Laurel family
which gave the compound its name. Megaphone has also been prepared synthetically.
Studies carried out in the 1960s demonstrated that an alcoholic extract of the ground root of Aniba megaphylla inhibited, in vitro, growth of cells derived from human carcinoma
of the nasopharynx
. In 1978, the active components of the extract were isolated using silica gel
chromatography
, characterized and named as megaphone (C22H30O6, solid), megaphone acetate
(C24H32O7, oily liquid) and megaphyllone acetate (C23H28O7, oily liquid). For comparison, megaphone acetate was also produced synthetically by reacting megaphone with acetic anhydride
at 50 °C for 6 hours. Stirring an alcoholic solution of megaphone (megaphone acetate), with added palladium catalyst, in hydrogen atmosphere, followed by evaporation of the solvent yields tetrahydromegaphone (tetrahydromegaphone acetate) as an oil. Millimeter-sized crystals of megaphone can be grown from an ether
-chloroform
solution. They have monoclinic symmetry with space group
P21, lattice constants a = 0.8757 nm, b = 1.1942 nm and c = 1.0177 nm and two formula unit
s per unit cell. Megaphone and megaphone acetate molecules are chiral
and the reported extraction and synthesis procedures yielded their racemic mixtures. Megaphone acetate was also isolated from the root of Endlicheria dysodantha, another plant of Laurel family
, using chromatography of ethanolic solution. It showed inhibitory activity against cells of crown gall tumor and human lung, breast and colon carcinomas.
Cytotoxicity
Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are a chemical substance, an immune cell or some types of venom .-Cell physiology:...
neolignan obtained from Aniba megaphylla
Aniba megaphylla
Aniba megaphylla is a plant in the genus Aniba. The plant produces the cytotoxic lignan megaphone.-External links:*...
, a flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
of Laurel family
Lauraceae
The Lauraceae or Laurel family comprises a group of flowering plants included in the order Laurales. The family contains about 55 genera and over 3500, perhaps as many as 4000, species world-wide, mostly from warm or tropical regions, especially Southeast Asia and South America...
which gave the compound its name. Megaphone has also been prepared synthetically.
Studies carried out in the 1960s demonstrated that an alcoholic extract of the ground root of Aniba megaphylla inhibited, in vitro, growth of cells derived from human carcinoma
Carcinoma
Carcinoma is the medical term for the most common type of cancer occurring in humans. Put simply, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that generally arises from cells originating in the endodermal or ectodermal germ layer during...
of the nasopharynx
Nasopharynx
The nasopharynx is the uppermost part of the pharynx. It extends from the base of the skull to the upper surface of the soft palate; it differs from the oral and laryngeal parts of the pharynx in that its cavity always remains patent .-Lateral:On its lateral wall is the pharyngeal ostium of the...
. In 1978, the active components of the extract were isolated using silica gel
Silica gel
Silica gel is a granular, vitreous, porous form of silica made synthetically from sodium silicate. Despite its name, silica gel is a solid. It is a naturally occurring mineral that is purified and processed into either granular or beaded form...
chromatography
Chromatography
Chromatography is the collective term for a set of laboratory techniques for the separation of mixtures....
, characterized and named as megaphone (C22H30O6, solid), megaphone acetate
Acetate
An acetate is a derivative of acetic acid. This term includes salts and esters, as well as the anion found in solution. Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In...
(C24H32O7, oily liquid) and megaphyllone acetate (C23H28O7, oily liquid). For comparison, megaphone acetate was also produced synthetically by reacting megaphone with acetic anhydride
Acetic anhydride
Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula 2O. Commonly abbreviated Ac2O, it is the simplest isolatable acid anhydride and is a widely used reagent in organic synthesis...
at 50 °C for 6 hours. Stirring an alcoholic solution of megaphone (megaphone acetate), with added palladium catalyst, in hydrogen atmosphere, followed by evaporation of the solvent yields tetrahydromegaphone (tetrahydromegaphone acetate) as an oil. Millimeter-sized crystals of megaphone can be grown from an ether
Ether
Ethers are a class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups — of general formula R–O–R'. A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether"...
-chloroform
Chloroform
Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous...
solution. They have monoclinic symmetry with space group
Space group
In mathematics and geometry, a space group is a symmetry group, usually for three dimensions, that divides space into discrete repeatable domains.In three dimensions, there are 219 unique types, or counted as 230 if chiral copies are considered distinct...
P21, lattice constants a = 0.8757 nm, b = 1.1942 nm and c = 1.0177 nm and two formula unit
Formula unit
A formula unit in chemistry is the empirical formula of an ionic or covalent network solid compound used as an independent entity for stoichiometric calculations. It is the lowest whole number ratio of ions represented in an ionic compound...
s per unit cell. Megaphone and megaphone acetate molecules are chiral
Chirality (chemistry)
A chiral molecule is a type of molecule that lacks an internal plane of symmetry and thus has a non-superimposable mirror image. The feature that is most often the cause of chirality in molecules is the presence of an asymmetric carbon atom....
and the reported extraction and synthesis procedures yielded their racemic mixtures. Megaphone acetate was also isolated from the root of Endlicheria dysodantha, another plant of Laurel family
Lauraceae
The Lauraceae or Laurel family comprises a group of flowering plants included in the order Laurales. The family contains about 55 genera and over 3500, perhaps as many as 4000, species world-wide, mostly from warm or tropical regions, especially Southeast Asia and South America...
, using chromatography of ethanolic solution. It showed inhibitory activity against cells of crown gall tumor and human lung, breast and colon carcinomas.