| slovo | definícia |
CH2CH
(gcide) | Ethenyl \Eth"e*nyl\, n. [Ethene + -yl.] (Chem.)
(a) A trivalent hydrocarbon radical, CH3.C.
(b) A univalent hydrocarbon radical of the ethylene series,
CH2:CH; -- called also vinyl. See Vinyl.
[1913 Webster] |
| | podobné slovo | definícia |
CH2CH
(gcide) | Ethenyl \Eth"e*nyl\, n. [Ethene + -yl.] (Chem.)
(a) A trivalent hydrocarbon radical, CH3.C.
(b) A univalent hydrocarbon radical of the ethylene series,
CH2:CH; -- called also vinyl. See Vinyl.
[1913 Webster] |
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] |
CH32CHCH2CHNH2-COOH
(gcide) | Leucine \Leu"cine\ (l[=oo]"s[=e]n), Leucin
\Leu"cin\(l[=u]"s[i^]n), n. [Gr. leyko`s white.] (Physiol.
Chem.)
a naturally occurring alpha-amino acid
((CH3)2CH.CH2.CH(NH2)-COOH), one of the building units of
almost all proteins of living organisms, both animal and
vegetable. It is one of the essential amino acids (not
synthesized by the human body, a required component for
proper nutrition), and is hydrophobic in character when bound
in proteins. In isolated form it is a white, crystalline,
zwitterionic substance formed, e. g. by the decomposition of
proteins by pancreatic digestion, by the action of boiling
dilute mineral acid, or by putrefaction. Chemically it is to
be considered as amido-caproic acid. It occurs as two optical
isomers, the L- and D-forms. The L-form, L-leucine, is the
natural form, present in most proteins.
[1913 Webster +PJC] |
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] |
CH3CH25CHOHCH2CHCHCH27COOH
(gcide) | ricinoleic acid \ric`in*o"le*ic ac"id\, n. (Chem.)
An organic acid (C18H34O3) obtained from the castor-oil
plant (Ricinus communis, or Palma Christi) and other
species of the family Euphorbiaceae; chemicaly it is
d-12-hydroxyoleic acid
(CH3(CH2)5.CH(OH).CH2.CH=CH.(CH2)7COOH). Formerly called
palmic acid.
[1913 Webster +PJC] |
CH3CH2CH
(gcide) | Propidene \Pro"pi*dene\, n. [Propyl + ethylidene.] (Chem.)
The unsymmetrical hypothetical hydrocarbon radical,
CH3.CH2.CH, analogous to ethylidene, and regarded as the
type of certain derivatives of propane; -- called also
propylidene.
[1913 Webster] |
HOCH2CHNH2COOH
(gcide) | Serine \Ser"ine\ (s[e^]r"[=e]n; s[e^]r"[i^]n; also, less
correctly, s[=e]r"[=e]n), n. [L. sericus silken.] (Chem.)
one of the natural L-amino acids, obtainable as a white
crystalline nitrogenous substance by the action of dilute
sulphuric acid on silk gelatin. It is found in many proteins,
and, having a free primary hydroxyl group on the side chain,
is involved in the catalytic action at the active site of
some enzymes, such as proteases. The IUPAC abbreviation for
serine in protein sequences is Ser. Chemically it is
2-amino-3-hydroxy-propanoic acid (C3H7NO3),
HO.CH2.CH(NH2).COOH.
[1913 Webster +PJC] Serio-comic |
HOCH2CHOH4CH2OH
(gcide) | mannitol \man"ni*tol\, n. [Mannite + -ol.]
1. (Chem.) A white crystalline hexose
(HO.CH2.(CHOH)4.CH2.OH) of a sweet taste obtained from a
so-called manna, the dried sap of the flowering ash
(Fraxinus ornus); -- called also mannite, and {hydroxy
hexane}. Cf. Dulcite. It is used in pharmacy as
excipient and diluent for solids and liquids. It is also
used as a food additive for anti-caking properties, or as
a sweetener, and, illegally, to "cut" (dilute) illegal
drugs such as cocaine or heroin.
Syn: D-mannitol; manna sugar; cordycepic acid; Diosmol;
Mannicol; Mannidex; Osmiktrol; Osmosal.
[1913 Webster +PJC] |
HOCOCH2CHOHCOOH
(gcide) | Malic \Ma"lic\, a. [L. malum an apple: cf. F. malique.] (Chem.)
Pertaining to, or obtained from, apples; as, malic acid.
[1913 Webster]
Malic acid, (Chem.) a hydroxy acid
(HO.CO.CH2.CH(OH).CO.OH) obtained from unripe fruit
(such as green apples, currants, tomatoes or cherries) as
a substance which is sirupy or crystallized with
difficulty, and has a strong but pleasant sour taste. It
is levorotatory or dextrorotatory according to the
temperature and concentration; the natural form is of L-
conformation. A synthetic variety is a derivative of
succinic acid, but as with most simple synthetic
compounds, is a racemic mixture of isomers and thus has no
rotatory action on polarized light.
[1913 Webster +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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