Valacyclovir HCl

    WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 318966

CAS#: 124832-27-5 (HCl)

Description: Valacyclovir is a nucleoside analogue DNA polymerase inhibitor. Valacyclovir is rapidly converted to acyclovir which has demonstrated antiviral activity against HSV types 1 (HSV-1) and 2 (HSV-2) and VZV both in cell culture and in vivo. The EC50 values against herpes simplex virus isolates range from 0.09 to 60 μM (0.02 to 13.5 mcg/mL) for HSV-1 and from 0.04 to 44 μM (0.01 to 9.9 mcg/mL) for HSV-2. The EC50 values for acyclovir against most laboratory strains and clinical isolates of VZV range from 0.53 to 48 μM (0.12 to 10.8 mcg/mL). Acyclovir also demonstrates activity against the Oka vaccine strain of VZV with a mean EC50 of 6 μM (1.35 mcg/mL).

Chemical Structure

Valacyclovir HCl
CAS# 124832-27-5 (HCl)

Theoretical Analysis

MedKoo Cat#: 318966
Name: Valacyclovir HCl
CAS#: 124832-27-5 (HCl)
Chemical Formula: C13H21ClN6O4
Exact Mass: 0.00
Molecular Weight: 360.799
Elemental Analysis: C, 43.28; H, 5.87; Cl, 9.83; N, 23.29; O, 17.74

Price and Availability

Size Price Availability Quantity
20g USD 1450
2g USD 450
5g USD 650
50g USD 1950
1g USD 250
10g USD 1050
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Related CAS #: 124832-26-4 (free base), 124832-27-5 (HCl), 950189-66-9 (maleate),

Synonym: 256U; 256U87; Vacyclovir, L-valyl ester; BW256U87; L-valylacyclovir; Valacyclovir Hydrochloride; Valtrex; Zelitrex.

IUPAC/Chemical Name: 2-[(2-amino-6-oxo-3H-purin-9-yl)methoxy]ethyl (2S)-2-amino-3-methylbutanoate hydrochloride


InChi Code: InChI=1S/C13H20N6O4.ClH/c1-7(2)8(14)12(21)23-4-3-22-6-19-5-16-9-10(19)17-13(15)18-11(9)20;/h5,7-8H,3-4,6,14H2,1-2H3,(H3,15,17,18,20);1H/t8-;/m0./s1


Appearance: White solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: Soluble in DMSO, not in water

Shelf Life: >2 years if stored properly

Drug Formulation: This drug may be formulated in DMSO

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

Product Data:

Preparing Stock Solutions

The following data is based on the product molecular weight 360.799000000000000000000000000000 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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1: Acyclovir versus Valacyclovir for Herpes Virus in Children and Pregnant Women: A Review of the Clinical Evidence and Guidelines [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2014 Sep 05. Available from PubMed PMID: 25411683. 2: Reischig T, Kacer M. The efficacy and cost-effectiveness of valacyclovir in cytomegalovirus prevention in solid organ transplantation. Expert Rev Pharmacoecon Outcomes Res. 2014 Dec;14(6):771-9. doi: 10.1586/14737167.2014.965157. Epub 2014 Sep 25. Review. PubMed PMID: 25252996. 3: Rajalakshmi R, Kumari R, Thappa DM. Acyclovir versus valacyclovir. Indian J Dermatol Venereol Leprol. 2010 Jul-Aug;76(4):439-44. doi: 10.4103/0378-6323.66577. Review. PubMed PMID: 20657140. 4: Vigil KJ, Chemaly RF. Valacyclovir: approved and off-label uses for the treatment of herpes virus infections in immunocompetent and immunocompromised adults. Expert Opin Pharmacother. 2010 Aug;11(11):1901-13. doi: 10.1517/14656566.2010.494179. Review. PubMed PMID: 20536295. 5: Asahi T, Tsutsui M, Wakasugi M, Tange D, Takahashi C, Tokui K, Okazawa S, Okudera H. Valacyclovir neurotoxicity: clinical experience and review of the literature. Eur J Neurol. 2009 Apr;16(4):457-60. doi: 10.1111/j.1468-1331.2008.02527.x. Review. PubMed PMID: 19187258. 6: Brantley JS, Hicks L, Sra K, Tyring SK. Valacyclovir for the treatment of genital herpes. Expert Rev Anti Infect Ther. 2006 Jun;4(3):367-76. Review. PubMed PMID: 16771614. 7: Chakrabarty A, Anderson NJ, Beutner R, Tyring SK. Valacyclovir for the management of herpes viral infections. Skin Therapy Lett. 2005 Feb;10(1):1-4. Review. PubMed PMID: 15776202. 8: Wu JJ, Brentjens MH, Torres G, Yeung-Yue K, Lee P, Tyring SK. Valacyclovir in the treatment of herpes simplex, herpes zoster, and other viral infections. J Cutan Med Surg. 2003 Sep-Oct;7(5):372-81. Epub 2003 Sep 24. Review. PubMed PMID: 14505192. 9: Lerner AM, Beqaj SH, Deeter RG, Dworkin HJ, Zervos M, Chang CH, Fitzgerald JT, Goldstein J, O'Neill W. A six-month trial of valacyclovir in the Epstein-Barr virus subset of chronic fatigue syndrome: improvement in left ventricular function. Drugs Today (Barc). 2002 Aug;38(8):549-61. Review. PubMed PMID: 12582420. 10: Griffiths PD. Tomorrow's challenges for herpesvirus management: potential applications of valacyclovir. J Infect Dis. 2002 Oct 15;186 Suppl 1:S131-7. Review. PubMed PMID: 12353198. 11: Squifflet JP, Legendre C. The economic value of valacyclovir prophylaxis in transplantation. J Infect Dis. 2002 Oct 15;186 Suppl 1:S116-22. Review. PubMed PMID: 12353196. 12: Tyring SK, Baker D, Snowden W. Valacyclovir for herpes simplex virus infection: long-term safety and sustained efficacy after 20 years' experience with acyclovir. J Infect Dis. 2002 Oct 15;186 Suppl 1:S40-6. Review. PubMed PMID: 12353186. 13: Baker DA. Valacyclovir in the treatment of genital herpes and herpes zoster. Expert Opin Pharmacother. 2002 Jan;3(1):51-8. Review. PubMed PMID: 11772333. 14: Dekker CL, Prober CG. Pediatric uses of valacyclovir, penciclovir and famciclovir. Pediatr Infect Dis J. 2001 Nov;20(11):1079-81. Review. PubMed PMID: 11734715. 15: Biernat-Sudolska M. [Valacyclovir]. Przegl Lek. 1998;55(11):596-8. Review. Polish. PubMed PMID: 10216374. 16: Grose C, Wiedeman J. Generic acyclovir vs. famciclovir and valacyclovir. Pediatr Infect Dis J. 1997 Sep;16(9):838-41. Review. PubMed PMID: 9306476. 17: Stein GE. Pharmacology of new antiherpes agents: famciclovir and valacyclovir. J Am Pharm Assoc (Wash). 1997 Mar-Apr;NS37(2):157-63. Review. PubMed PMID: 9069689. 18: Acosta EP, Fletcher CV. Valacyclovir. Ann Pharmacother. 1997 Feb;31(2):185-91. Review. PubMed PMID: 9034421. 19: Raffi F. [Future prospects of valacyclovir in treating and preventing herpesviridae infections in immunosuppressed patients]. Presse Med. 1997 Jan;26 Suppl 1:19-21. Review. French. PubMed PMID: 9082437. 20: Smiley ML, Murray A, de Miranda P. Valacyclovir HCl (Valtrex): an acyclovir prodrug with improved pharmacokinetics and better efficacy for treatment of zoster. Adv Exp Med Biol. 1996;394:33-9. Review. PubMed PMID: 8815698.