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CAS#: 1038915-64-8 (HCl)

Description: Niraparib, also know as MK-4827, is an inhibitor of poly (ADP-ribose) polymerase (PARP) with potential antineoplastic activity. MK4827 inhibits PARP activity, enhancing the accumulation of DNA strand breaks and promoting genomic instability and apoptosis. The PARP family of proteins detect and repair single strand DNA breaks by the base-excision repair (BER) pathway. The specific PARP family member target for PARP inhibitor MK4827 is unknown.

Synonym: MK4827; MK 4827; MK4827; Niraparib; Niraparib HCl; Niraparib hydrochloride.

IUPAC/Chemical Name: (S)-2-(4-(piperidin-3-yl)phenyl)-2H-indazole-7-carboxamide hydrochloride


Size                                                      Price

10mg                                                 Not available
100mg                                              Not available
1g                                                      Ask price
Niraparib HCl, purity > 98%, is not in stock, may be available through custom synthesis. Minimum 1 gram order is requested. Current shipping out time is about 70 days after order is received.


Name: Niraparib HCl
CAS#: 1038915-64-8 (HCl)
Chemical Formula: C19H21ClN4O
Exact Mass: 356.1404
Molecular Weight: 356.854
Elemental Analysis: C, 63.95; H, 5.93; Cl, 9.93; N, 15.70; O, 4.48


Solid powder
>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).
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).


Related CAS#
CAS#1038915-60-4 ( Niraparib free base);
CAS#1038915-64-8 ( Niraparib HCl salt);
CAS#1038915-73-9 ( Niraparib tosylate)

MK-4827 displays good pharmacokinetic properties and is currently in phase I clin. trials. This compd. displays excellent PARP 1 and 2 inhibition with IC50 = 3.8 and 2.1 nM, resp., and in a whole cell assay, it inhibited PARP activity with EC50 = 4 nM and inhibited proliferation of cancer cells with mutant BRCA-1 and BRCA-2 with CC50 in the 10-100 nM range. MK-4827 was well tolerated in vivo and demonstrated efficacy as a single agent in a xenograft model of BRCA-1 deficient cancer.  [See: Journal of Medicinal Chemistry (2009), 52(22), 7170-7185. ]

MK-4827 was found to be highly and similarly effective in both radiation schedules but maximum radiation enhancement was observed when MK-4827 was given at a dose of 50 mg/kg once daily (EF = 2.2). MK-4827 radiosensitized all four tumors studied regardless of their p53 status. MK-4827 reduced PAR levels in tumors by 1 h after administration which persisted for up to 24 h. This long period of PARP inhibition potentially adds to the flexibility of design of future clinical trials. Thus, MK-4827 shows high potential to improve the efficacy of radiotherapy. (source: Invest New Drugs. 2011 Nov 30. [Epub ahead of print])


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