Michellamines are a group of
atropisomer
Atropisomers are stereoisomers arising because of hindered rotation about a covalent bond, single bond, where Gibbs free energy, energy differences due to steric strain or other contributors create a barrier to rotation that is high enough to all ...
ic
alkaloid
Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids.
Alkaloids are produced by a large varie ...
which have been found to be HIV viral replication inhibitors ''
in vitro
''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...
''. It was discovered in the leaves of ''
Ancistrocladus korupensis''. There are three michellamines represented as A, B, and C; however, michellamine B is the most active against the NID-DZ strain of
HIV-2
The subtypes of HIV include two main subtypes, known as HIV type 1 (HIV-1) and HIV type 2 (HIV-2). These subtypes have distinct genetic differences and are associated with different epidemiological patterns and clinical characteristics.
HIV-1 ex ...
.
Occurrence
Michellamine A and B occur naturally in ''Ancistrocladus korupensis'' leaves. Other chemical substances including
alkaloids
Alkaloids are a broad class of naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids.
Alkaloids are produced by a large variety of organisms i ...
,
tannins
Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids. The term ''tannin'' is widely applied to any large po ...
, and
saponin
Saponins (Latin ''sapon'', 'soap' + ''-in'', 'one of') are bitter-tasting, usually toxic plant-derived secondary metabolites. They are organic chemicals that become foamy when agitated in water and have high molecular weight. They are present ...
s are found in the roots, leaves, stems, flowers, or bark.
Synthesis
There are two methods explored to synthesize michellamines A and B. The first one, originally synthesized in 1994, is a retrosynthesis that leads to a
biomimetic
Biomimetics or biomimicry is the emulation of the models, systems, and elements of nature for the purpose of solving complex human problems. The terms "biomimetics" and "biomimicry" are derived from (''bios''), life, and μίμησις ('' mīm ...
pathway that uses the construction of
naphthalene
Naphthalene is an organic compound with formula . It is the simplest polycyclic aromatic hydrocarbon, and is a white Crystal, crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 Parts-per notation ...
/
isoquinoline
Isoquinoline is an individual chemical specimen - a heterocyclic aromatic organic compound - as well as the name of a family of many thousands of natural plant alkaloids, any one of which might be referred to as "an isoquinoline". It is a struc ...
bonds before the naphthalene/naphthalene axis. The second method, originally synthesized only a few montes after the first method, is a complementary pathway that would use the naphthalene/naphthalene axis after it is created and add the two
isoquinoline
Isoquinoline is an individual chemical specimen - a heterocyclic aromatic organic compound - as well as the name of a family of many thousands of natural plant alkaloids, any one of which might be referred to as "an isoquinoline". It is a struc ...
moieties.
Research
Michellamines inhibit
protein kinase C
In cell biology, protein kinase C, commonly abbreviated to PKC (EC 2.7.11.13), is a family of protein kinase enzymes that are involved in controlling the function of other proteins through the phosphorylation of hydroxyl groups of serine and t ...
and virus-induced cellular fusion.
They have a broad range of effectiveness ''
in vitro
''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...
'' across most HIV strains, particularly the
HIV-2
The subtypes of HIV include two main subtypes, known as HIV type 1 (HIV-1) and HIV type 2 (HIV-2). These subtypes have distinct genetic differences and are associated with different epidemiological patterns and clinical characteristics.
HIV-1 ex ...
strain, which is found primarily in and around
Cameroon
Cameroon, officially the Republic of Cameroon, is a country in Central Africa. It shares boundaries with Nigeria to the west and north, Chad to the northeast, the Central African Republic to the east, and Equatorial Guinea, Gabon, and the R ...
.
References
{{reflist
HIV/AIDS
Tetrahydroisoquinoline alkaloids