Abacavir Chemical Properties

Melting point:

165°

alpha 

D20 -59.7°; 43620 -127.8°; 36520 -218.1° (c = 0.15 in methanol)

Boiling point:

636.0±65.0 °C(Predicted)

Density 

1.70±0.1 g/cm3(Predicted)

storage temp. 

Sealed in dry,2-8°C

solubility 

DMSO (Slightly, Heated), Methanol (Slightly)

pka

5.01(at 25℃)

form 

Solid

color 

Off-White to Pale Beige

Merck 

14,1

BCS Class

3

CAS DataBase Reference

136470-78-5(CAS DataBase Reference)

EPA Substance Registry System

2-Cyclopentene-1-methanol, 4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-, (1S,4R)- (136470-78-5)

Safety Information

RTECS 

GY5979200

HS Code 

2933.99.7500

Abacavir Usage And Synthesis

Description

The drug is extensively metabolized via stepwise phosphorylation to 5′-mono-, di-, and triphosphate. Abacavir is well absorbed (>75%) and penetrates the CNS. The drug can be taken without regard to meals. The drug does not show any clinically significant drug–drug interactions. Abacavir has been reported to produce life-threatening hypersensitivity reactions. The major use of abacavir appears to be in combination with other nucleoside RT inhibitors. A fixed-combination product has recently been approved by the U.S. FDA consisting of 300 mg of ABC, 150 mg of 3TC, and 300 mg of ZDV (Trizivar). The combination has been shown to be superior to other combinations in reducing viral load as well as to show improvement in CD4 cell count.

Originator

Ziagen ,GlaxoSmithKline

Uses

A nucleoside reverse transcriptase inhibitor (NRTI).

Uses

Abacavir is a commonly used nucleoside analogue with potent antiviral activity against HIV-1. - See more at: http://www.selleckchem.com/products/abacavir-sulfate.html#sthash.lApvcTNO.dpuf

Indications

Abacavir (Ziagen) is a guanosine nucleoside analogue indicated for the therapy of HIV-1 infection in adults and children. It is used as part of a multidrug regimen and is available in a fixed-dose combination with zidovudine and lamivudine (Trizivir). It is also used for postexposure HIV infection prophylaxis.

Definition

ChEBI: Abacavir is a 2,6-diaminopurine that is (1S)-cyclopent-2-en-1-ylmethanol in which the pro-R hydrogen at the 4-position is substituted by a 2-amino-6-(cyclopropylamino)-9H-purin-9-yl group. A nucleoside analogue reverse transcriptase inhibitor (NRTI) with antiretroviral activity against HIV, it is used (particularly as the sulfate) with other antiretrovirals in combination therapy of HIV infection. It has a role as a HIV-1 reverse transcriptase inhibitor, an antiviral drug and a drug allergen.

Manufacturing Process

Treatment of 2,5-diamino-4,6-dihydroxypyrimidine (I) with (chloromethylene)dimethylammonium chloride yielded the dichloropyrimidine with both amino groups derivatized as amidines. Partial hydrolysis with aqueous HCl in hot ethanol gave N-(2-amino-4,6-dichloro-pyrimidin-5-yl)-N,Ndimethylformamidene (II). Subseqent buffered hydrolysis at pH 3.2 yielded the (2-amino-4,6-dichloro-pyrimididin-5-ylamino)acetaldehyde (III). Condensation chloropyrimidine (III) with (1S,4R)-4-amino-2-cyclopentene-1- methanol (IV) in the presence of triethylamine and NaOH gave [2-amino-4- chloro-6-(4-hydroxymethyl-cyclopent-2-enylamino)pyrimidin-5-ylamino]- acetaldehyde (V). The correct enantiomer (IV) of racemic aminocyclopentene was obtained by resolution of diastereomeric salts with D-dibenzoyltartaric acid. Cyclization of (V) to the corresponding purine was accomplished with refluxing triethyl orthoformate or diethoxymethyl acetate to give nucleoside analogue [4-(2-amino-6-chloro-purin-9-yl)-cyclopent-2-enyl]methanol (VI). Displacement of chloride in the purine nucleus with cyclopropyl amine in refluxing butanol afforded abacavir. The structure of obtained compound was confirmed by 1H NMR method and elemental analysis.
In practice it is usually used as sulfate salt.

Therapeutic Function

Antiviral

Antimicrobial activity

Abacavir has activity against HIV-1, HIV-2 and human T-cell lymphotrophic virus type-1 (HTLV-1).

Acquired resistance

Resistance is associated with specific changes in codons 184 with 65, 74 or 115 in the HIV reverse transcriptase codon region.

General Description

Abacavir is a nucleoside reverse transcriptase inhibitorNRTI that has been approved for use in combination therapiesfor the treatment of HIV and AIDS. Once in the tissues,it is metabolized by stepwise phosphorylation to themonophosphate, diphosphate, and triphosphate. Abacavir ishighly bioavailable (＞75%) and is effective by the oralroute. It penetrates the blood-brain barrier efficiently.Abacavir has been reported to produce life-threatening hypersensitivityreactions in some patients.

Pharmaceutical Applications

A synthetic analog of guanine formulated for oral use.

Pharmacokinetics

Oral absorption: 83%
C_max 300 mg oral, twice daily: 3.0 ± 0.89 mg/L
600 mg once daily: 4.26 mg/L
Plasma half-life: 1.5 h
Volume of distribution: 0.8 L/kg
Plasma protein binding: c. 49%
Absorption
After oral administration abacavir sulfate undergoes rapid and extensive absorption unaffected by food.
Distribution
It penetrates well into the cerebrospinal fluid (CSF) and is an NRTI of choice if this characteristic is thought desirable. Good penetration into the male genital tract has been observed. The drug is secreted into human breast milk.
Metabolism
It is primarily metabolized in the liver, mainly by alcohol dehydrogenase and glucuronidation.
Excretion
Around 83% of the dose is eliminated in the urine, <2% as unchanged drug; the remainder is excreted in the feces. Dose adjustment is unnecessary in renal impairment. It can be used in moderate hepatic impairment, but is contraindicated if dysfunction is severe.

Clinical Use

Treatment of HIV infection in adults and children (in combination with other antiretroviral drugs)

Side effects

Abacavir is associated with side effects such as anorexia, nausea, vomiting, malaise, headache, and insomnia. A potentially fatal hypersensitivity reaction develops in approximately 5% of patients, usually early in the course of treatment. Fever and rash are the most common symptoms of this reaction; malaise, respiratory symptoms, and gastrointestinal complaints may also occur. Resistance to abacavir may be associated with resistance to zidovudine, didanosine, and lamivudine.

Side effects

Life-threatening hypersensitivity reactions occur in 5–8% of all individuals, necessitating discontinuation of the drug. Typically patients present within the first 6 weeks of starting treatment with fever, rash or other symptoms that worsen in severity with continued drug exposure. Hypersensitivity is associated with carriage of the major histocompatibility complex class I allele HLA-B57*01 and screening for this allele can significantly reduce the incidence of this effect.
Current or recent (within the preceding 6 months) use of abacavir has been associated with a risk of myocardial infarction, but studies have yielded conflicting data.

Drug interactions

Potentially hazardous interactions with other drugs
Antivirals: possibly reduces effects of ribavirin; concentration reduced by tipranavir.
Orlistat: absorption possibly reduced by orlistat.

Metabolism

Abacavir is primarily metabolised by the liver with approximately 2% of the administered dose being renally excreted, as unchanged compound. The primary pathways of metabolism in man are by alcohol dehydrogenase and by glucuronidation to produce the 5'-carboxylic acid and 5'-glucuronide which account for about 66% of the administered dose. The metabolites are excreted in the urine.

Abacavir(136470-78-5)Related Product Information

• EC 2.6.1.2
• Methyl cyclopentenolone
• Glycine
• 4-Amino-benzenesulfonic acid monosodium salt
• 6-Aminocaproic acid
• ALTRENOGEST
• Tris(hydroxymethyl)aminomethane
• Acetaminophen
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• Sulfamic acid
• Cyclopentene
• ABACAVIR SULFATE,ABACAVIR SULPHATE
• N-(2-AMINO-4,6-DICHLOROPYRIMIDIN-5-YL) FORMAMIDE[FOR ABACAVIR]
• (1S-cis)-4-Amino-2-cyclopentene-1-methanol
• Purine
• Abacavir
• trans-Abacavir Hydrochloride
• Abacavir Related CoMpound D