| slovo | definícia |
CH2CH2
(gcide) | Ethylidene \E*thyl"i*dene\ (Chem.)
An unsymmetrical, divalent, hydrocarbon radical, C2H4
metameric with ethylene but written thus, CH3.CH= to
distinguish it from the symmetrical ethylene, CH2=CH2. Its
compounds are derived from aldehyde. Formerly called also
ethidene.
[1913 Webster] |
| | podobné slovo | definícia |
CH33NCH2CH2OCOCH3OH-
(gcide) | acetylcholine \acetylcholine\ n.
1. a neurotransmitter released by the transmitting dendron at
autononmous synapses and at neuromuscular junctions. It is
a quaternary amine with an obligatory negative counterion.
The nominal formula for the hydroxide form is C7H17NO3.
Structural formula (CH3)3N(+)CH2CH2.O.CO.CH3.OH(-).
Note: Acetylcholine is the first recognized and best-studied
of the neurotransmitters. At receptors it is recycled
into choline by the action of acetylcholinesterase.
Acetylcholinesterase inhibitors therefore function as
nerve poisons. For biochemical studies it is prepared
typically in the chloride or bromide forms.
[WordNet 1.5 +PJC] |
ROCH2CHOR'CH2OPO2OCH2CH2NH2
(gcide) | cephalin \ceph"a*lin\ (k[e^]f"[.a]*l[i^]n), n. [Gr. kefalh` the
head; it was supposed by Thudichum to exist in brain tissue.]
(Physiol. Chem.)
One of a group of phospholipids (nitrogenous phosphorized
fatty substances), present in all living cells and
particularly evident in nervous tissue. The cephalins consist
of glycerol phosphate in which the two free hydroxyls of the
glycerol are esterified with fatty acids, and the phosphate
forms an ester linkage to the hydroxyl of ethanolamine. The
phosphate may be linked to the alpha (end) or beta (middle)
hydroxyl of the glycerol portion. The natural isomers are of
the alpha form, and have the general formula
R.O.CH2.CHOR'.CH2.O.PO2.O.CH2.CH2.NH2, where R and R' are
the acyl residues of long-chain fatty acids, which may be the
same or different. [Also spelled kephalin.]
Syn: phosphatidylethanolamine. [PJC] |
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