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Levodopa

Levodopa ??? ???
?? ??:
59-92-7
???(??):
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???:
Levodopa
???(??):
L-DOPA;3,4-DIHYDROXY-L-PHENYLALANINE;L-3,4-DIHYDROXYPHENYLALANINE;DIHYDROXYPHENYLALANINE;L-Dihydroxyphenylalanine;Levedopa;Dopar;Bendopa;Larodopa;3-HYDROXY-L-TYROSINE
CBNumber:
CB2402938
???:
C9H11NO4
??? ??:
197.19
MOL ??:
59-92-7.mol
MSDS ??:
SDS

Levodopa ??

???
276-278 °C (lit.)
?? ?
334.28°C (rough estimate)
??
-11.7 º (c=5.3, 1N HCl)
??
1.3075 (rough estimate)
???
-12 ° (C=5, 1mol/L HCl)
?? ??
2-8°C
???
??? ?? ???? ????? ?? ???? ????(96%). 1M ???? ? ?? 0.1M ???? ?? ?? ????.
?? ?? (pKa)
2.32(at 25℃)
??? ??
??? ??
??
???? ???
??
100.00%??. ?? ??
?? ??
?? ??
optical activity
-39.5 (H2O) -12.025 (1 mol dm-3 HCl)
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?? ?? ???? ?? ??? ???. ???? ???.
Merck
14,5464
BRN
2215169
???
????. ?? ???? ???? ????. ?? ??? ?????.
InChIKey
WTDRDQBEARUVNC-LURJTMIESA-N
LogP
-1.154 (est)
CAS ??????
59-92-7(CAS DataBase Reference)
NIST
Levodopa(59-92-7)
EPA
Levodopa (59-92-7)
??
  • ?? ? ?? ??
  • ?? ? ???? ?? (GHS)
??? ?? Xn
?? ???? ?? 22-36/37/38-20/21/22
????? 26-36-24/25
WGK ?? 3
RTECS ?? AY5600000
F ?????? 10-23
TSCA Yes
HS ?? 29225090
?? ?? ??? 59-92-7(Hazardous Substances Data)
?? LD50 in mice (mg/kg): 3650 ±327 orally, 1140 ±66 i.p., 450 ±42 i.v., >400 s.c.; in male, female rats (mg/kg): >3000, >3000 orally; 624, 663 i.p.; >1500, >1500 s.c. (Clark)
???? ?? KE-10853
????(GHS): GHS hazard pictograms
?? ?: Warning
??·?? ??:
?? ??·?? ?? ?? ?? ?? ?? ? ?? ?? P- ??
H302 ??? ??? ?? ?? ?? - ?? ?? 4 ?? GHS hazard pictograms P264, P270, P301+P312, P330, P501
H315 ??? ??? ??? ????? ?? ????? ?? 2 ?? GHS hazard pictograms P264, P280, P302+P352, P321,P332+P313, P362
H319 ?? ?? ??? ??? ?? ? ?? ?? ??? ?? ?? 2A ?? GHS hazard pictograms P264, P280, P305+P351+P338,P337+P313P
H335 ?? ???? ??? ? ?? ?? ???? ?? - 1? ??;???? ?? ?? 3 ?? GHS hazard pictograms
??????:
P261 ??·?·??·???·??·...·????? ??? ????.
P264 ?? ??? ?? ??? ????.
P264 ?? ??? ?? ??? ????.
P270 ? ??? ??? ??? ???, ???? ???? ???.
P301+P312 ??? ???? ??? ????(??)? ??? ????.
P302+P352 ??? ??? ??? ?? ????.
P305+P351+P338 ?? ??? ? ?? ?? ???? ????. ???? ?????? ?????. ?? ????.
NFPA 704
1
2 0

Levodopa MSDS


Levodopa

Levodopa C??? ??, ??, ??

??

Levodopa is an amino acid precursor of dopamine with antiparkinsonian properties. Levodopa is a prodrug that is converted to dopamine by DOPA decarboxylase and can cross the blood-brain barrier. When in the brain, levodopa is decarboxylated to dopamine and stimulates the dopaminergic receptors, thereby compensating for the depleted supply of endogenous dopamine seen in Parkinson's disease. To assure that adequate concentrations of levodopa reach the central nervous system, it is administered with carbidopa, a decarboxylase inhibitor that does not cross the blood-brain barrier, thereby diminishing the decarboxylation and inactivation of levodopa in peripheral tissues and increasing the delivery of dopamine to the CNS.

??? ??

L-Dopa [59-92-7], levodopa, crystallizes as colorless, odorless, and tasteless needles from water, mp 276-278℃(decomp.). It is freely soluble in dilute hydrochloric and formic acids but practically insoluble in ethanol, benzene, chloroform, and ethyl acetate. Solubility in water is 66 mg/40 mL. In the presence of moisture, l-dopa is rapidly oxidized by atmospheric oxygen, with darkening.

??

Levodopa is an immediate precursor of dopamine and product of tyrosine hydroxylase. It derived from vanillin is widely used for treatment of Parkinson’s disease, most often in combination with peripheral decarboxylase inhibitors such as benserazide and carbidopa.

??

ChEBI: Levodopa is an optically active form of dopa having L-configuration. Used to treat the stiffness, tremors, spasms, and poor muscle control of Parkinson's disease.

Biological Functions

Levodopa (L-DOPA), the most reliable and effective drug used in the treatment of parkinsonism, can be considered a form of replacement therapy. Levodopa is the biochemical precursor of dopamine. It is used to elevate dopamine levels in the neostriatum of parkinsonian patients. Dopamine itself does not cross the blood-brain barrier and therefore has no CNS effects. However, levodopa, as an amino acid, is transported into the brain by amino acid transport systems, where it is converted to dopamine by the enzyme L-aromatic amino acid decarboxylase.
If levodopa is administered alone, it is extensively metabolized by L-aromatic amino acid decarboxylase in the liver, kidney, and gastrointestinal tract. To prevent this peripheral metabolism, levodopa is coadministered with carbidopa (Sinemet), a peripheral decarboxylase inhibitor. The combination of levodopa with carbidopa lowers the necessary dose of levodopa and reduces peripheral side effects associated with its administration.

?? ??

Levodopa belongs to a group of the most effective drugs for treating the type of Parkinsonism not caused by medicinal agents. The first significant breakthrough in the treatment of PDcame about with the introduction of high-dose levodopa. Fahn referred to this as a revolutionary development intreating parkinsonian patients. The rationale for the use oflevodopa for the treatment of PD was established in theearly 1960s. Parkinsonian patients were shown to have decreasedstriatal levels of DA and reduced urinary excretionof DA. Since then, levodopa has shown to be remarkablyeffective for treating the symptoms of PD.

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Get medical help immediately if you have any symptoms: fever, unusual muscle stiffness, severe confusion, sweating, fast/irregular heartbeat, and rapid breathing. A severe allergic reaction to this drug is rare. This medication may cause saliva, urine, or sweat to turn dark. This effect is harmless.

Safety Profile

Poison by ingestion. Moderately toxic by intravenous and intraperitoneal routes. Human systemic effects by ingestion: somnolence, hallucinations and distorted perceptions, toxic psychosis, motor activity changes, ataxia, dyspnea. Experimental teratogenic and reproductive effects. Questionable human carcinogen producing skin tumors. Human mutation data reported. An anticholinergic agent used as an anti Parhnsonian drug. When heated to decomposition it emits toxic fumes of NOx

Purification Methods

Likely impurities are vanillin, hippuric acid, 3-methoxytyrosine and 3-aminotyrosine. DOPA recrystallises from large volumes of H2O forming colourless white needles; its solubility in H2O is 0.165%, but it is insoluble in EtOH, *C6H6, CHCl3, and EtOAc. Also crystallise it by dissolving it in dilute HCl and adding dilute ammonia to give pH 5, under N2. Alternatively, crystallise it from dilute aqueous EtOH. It is rapidly oxidised in air when moist, and darkens, particularly in alkaline solution. Dry it in vacuo at 70o in the dark, and store it in a dark container preferably under N2. It has at 220.5nm (log 3.79) and 280nm (log 3.42) in 0.001N max HCl. [Yamada et al. Chem Pharm Bull Jpn 10 693 1962, Bretschneider et al. Helv Chim Acta 56 2857 1973, NMR: Jardetzky & Jardetzky J Biol Chem 233 383 1958, Beilstein 4 IV 2492, 2493.]

Levodopa ?? ?? ? ???

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Levodopa ?? ??

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