GEMCITABINE

GEMCITABINE

95058-81-4

WeightAverage: 263.1981
Monoisotopic: 263.071762265

Chemical FormulaC₉H₁₁F₂N₃O₄

4-amino-1-[(2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)oxolan-2-yl]-1,2-dihydropyrimidin-2-one

Product Ingredients

• LY-188011
• LY188011

NECT

15. Hanzawa, Y.; Inazawa, K.; Kon, A.; Aoki, H.; Kobayashi, Y. Tetrahedron Lett. 1987, 28, 659–662. 16. Wirth, D. D. EP0727432, 1996

Synthesis Reference

John A. Weigel, “Process for making gemcitabine hydrochloride.” U.S. Patent US6001994, issued May, 1995.US6001994

Route 1

Reference：1. J. Org. Chem. 1988, 53, 2406-2409.

2. US4808614A.

Route 2

Reference：1. CN102417533A.

Route 3

Reference：1. Nucleosides, Nucleotides and Nucleic Acids 2010, 29, 113-122.

Route 4

Reference：1. CN102617677A.

Route 5

Reference：1. CN103012527A.

SYN

U.S. Patent No. 4,808,614 (the ‘614 patent) describes a process for synthetically producing gemcitabine, which process is generally illustrated in Scheme Scheme 1

5

SYN

U.S. Patent No. 4,965,374 (the ‘374 patent) describes a process for producing gemcitabine from an intermediate 3,5-dibenzoyl ribo protected lactone of the formula:

11 where the desired erythro isomer can be isolated in a crystalline form from a mixture of erythro and threo isomers. The process described in the ‘374 patent is generally outlined in Scheme 2.

Scheme 2

mixture of α and β anomers

SYN

U.S. Patent No. 5,521,294 (the ‘294 patent) describes l-alkylsulfonyl-2,2- difluoro-3 -carbamoyl ribose intermediates and intermediate nucleosides derived therefrom. The compounds are reportedly useful in the preparation of 2′-deoxy-2′,2’- difluoro-β-cytidine and other β-anomer nucleosides. The ‘294 patent teaches, inter alia, that the 3-hydroxy carbamoyl group on the difluororibose intermediate may enhance formation of the desired β-anomer nucleoside derivative. The ‘294 patent describes converting the lactone 4 to the dibenzoyl mesylate 13, followed by deprotection at the 3 position to obtain the 5-monobenzoyl mesylate intermediate 15, which is reacted with various isocyanates to obtain the compounds of formula 16. The next steps involve coupling and deprotection using methods similar to those described in previous patents. The process and the intermediates 15 and 16 are illustrated by scheme 3 below: Scheme 3

13 15

PhCOCK

PhNCO/TEA -o. -~- j*«0Ms

PhNHCOO -r F

16

1 coupling 2 deprotection

16 gemcitabine

CLIP

https://www.sciencedirect.com/science/article/abs/pii/S0008621514000500

PATENT

https://patents.google.com/patent/WO2008129530A1/en

e₃

13A deprotection isomer separation

deprotection

EXAMPLE 1

[0045] This example demonstrates the preparation of 2-deoxy-2,2-difluoro-D- ribofuranose-3,5-dicinnamate-l-p-toluenesulfonate.

[0046] Crude 2-deoxy-2,2-difluoro-D-riboufuranose-3,5-dicinnamate (2.5g, 6 mmol) was dissolved in dichloromethane (20 ml) in a round flask, and diethylamine (0.7g, 9.6 mmol) was added followed by p-toluenesulfonyl chloride (1.32 g, 6.92 mmol), which was added drop wise while cooling to 0-5⁰C. The mixture was stirred for 1 hour, and washed with IN HCl (15 ml), concentrated solution OfNaHCO₃ (15 ml), and dried over MgSO₄. The solvent was distilled off under reduced pressure to obtain crude 2-deoxy-2,2-difluoro-D-ribofuranose-3,5-dicinnamate-l-p- toluenesulfonate as light oil. Yield: 3.22 g, (5.6 mmol), 93%.

EXAMPLE 2

[0047] This example demonstrates the preparation of 3′,5′-dicinnamoyl-2′-deoxy- 2′,2′-difluorocytidine.

[0048] Dry 1 ,2-dichloroethane (800 ml) was added to N,O-bis(trimethylsilyl)- cytosine (136 g, 487 mmol) under nitrogen blanket to produce a clear solution, followed by adding trimethylsilyl triflate (Me₃SiOTf), (100 ml, 122.8 g, 520 mmol) and stirred for 30 minutes. A solution of 2-deoxy-2,2-difluoro-D-ribofuranose-3,5- dicinnamate-1-p-toluenesulfonate (128 g, 224 mmol) in 1 ,2-dichloroethane (400 ml) was added drop wise, and the mixture was refluxed overnight. After cooling, the solvent was distilled off to obtain crude 3,5-dicinnamoyl-N⁴-trimethylsilyl-2′-deoxy- 2′,2′-difluorocytidine as a light yellow solid. The residue was dissolved in ethyl acetate (1600 ml) and washed 3 times with water (3X400 ml). The ethyl acetate phase was mixed with concentrated solution OfNaHCO₃ (800 ml) for about 5 minutes, and then the mixture was set aside for about 20 minutes without stirring. The thus formed solid, which was precipitated in the inter-phase of the two layers, was filtered off and washed with 60 ml of ethyl acetate. The solid was dried under reduced pressure to obtain 116.7 g (223 mmol, 99.5%) of the crude 3′,5′-dicinnamoyl- 2′-deoxy-2′,2′- difluorocytidine containing 73.3 % of the β-anomer and 11.8 % of the α-anomer.

EXAMPLE 3

[0049] This example demonstrates the preparation of 3′,5′-dicinnamoyl-2′-deoxy- 2′,2′-difluorocytidine.

[0050] Dry 1,2-dichloroethane (1.5 L) was added to bis(trimethylsilyl)cytosine (417 g, 1.49 mol) under nitrogen blanket to produce a clear solution followed by adding trimethylsilyl triflate (Me₃SiOTf), (300 ml, 368.4 g, 1.56 mol) and stirred for 30 minutes. A solution of 2-deoxy-2,2-difluoro-D-ribofuranose-3,5-dicinnamate-l-p- toluenesulfonate (384 g, 673 mmol) in 1,2-dichloroethane (1.2 L) was added drop wise, and the mixture was refluxed overnight. After cooling, the solvent was distilled off to obtain crude 3,5-dicinnamoyl-N⁴-trimethylsilyl-2^l-deoxy-2′,2′-difluorocytidine as a light yellow solid. The residue was dissolved in ethyl acetate (2.4 L) and washed 3 times with water (3X1.2 L). The ethyl acetate phase was mixed with concentrated solution OfNaHCO₃ (1.34 L) for about 20 minutes. The thus formed solid, which was precipitated in the inter-phase of the two layers, was filtered off and washed with 180 ml of ethyl acetate. The solid was dried under reduced pressure to obtain 346.5 g (0.66 mol, 99.9% yield) of the crude 3^l,5^l-dicinnamoyl-2′-deoxy-2′,2′-difluorocytidine containing 43 % of the β-anomer and 52 % of the α-anomer.

EXAMPLE 4

[0051] This example demonstrates the preparation of gemcitabine hydrochloride. [0052] To a solution of ammonia-methanol (15.8 %, 4.57 L), the crude 3,5- dicirmamoyl-2′-deoxy-2′,2′-difluorocytidine of example 3 was added (346.5 g, 0.66 mol), and stirred at ambient temperature for 6 hours. The mixture was concentrated to afford a light yellow solid (306 g). Purified water (3 L) was added to the solid, followed by addition of ethyl acetate (1.8 L), and stirring was maintained for about 10 minutes. The aqueous layer was separated and the organic layer was extracted with water (1.05 L). The aqueous layers were combined and water was removed by evaporation under reduced pressure to obtain an oil (154.7 g). Water was added (660 ml) and the mixture was heated to 50-55⁰C to dissolve the solid. The mixture was cooled to 5-1O⁰C during about one hour and mixed for about 16 hours at that temperature. The thus formed solid was filtered and dried to afford 46.75 g (0.177 mol), containing 98 % of the β-anomer and 1.3 % of the α-anomer. 0.5N HCl (936 ml) was added followed by addition of dichloromethane (300 ml) with stirring. The water phase was separated and the aqueous phase was washed with dichloromethane (300 ml). After filtration, the aqueous phase was concentrated to dryness under reduced pressure to obtain gemcitabine hydrochloride as a solid (46.9 g). The solid was dissolved in water (187 ml) at ambient temperature and the mixture was heated to 50⁰C to afford a clear solution and cooled to ambient temperature. Acetone (1.4 L) was added and stirring was maintained for about one hour. Then, the precipitate was collected by filtration and washed twice with acetone (2X30 ml) and dried at 45⁰C under vacuum to obtain 39.2 g of gemcitabine hydrochloride, containing 99.9% of the β-anomer

EXAMPLE 5

[0053] This example demonstrates the preparation of gemcitabine hydrochloride. [0054] To a solution of ammonia-methanol (about 15.8 %, 1.35 L), the crude 3′,5′- dicinnamoyl-2′-deoxy-2′,2′-difluorocytidine prepared as described in example 2 was added (96 g, 183.4 mmol), and stirred at ambient temperature for 4 hours. The mixture was concentrated to afford a light yellow solid (80.5 g). Purified water (1 L) was added to the solid, followed by addition of ethyl acetate (600 ml), and stirring was maintained for about 10 minutes. The aqueous layer was separated and the organic layer was extracted with water (350 ml). The aqueous layers were combined and water was removed by evaporation under reduced pressure to obtain an oil (46.4 g). Water was added (220 ml) and the mixture was heated to 50-55⁰C to dissolve the solid. The mixture was cooled to 0-5⁰C during about one hour and mixed for about 16 hours at that temperature. The thus formed solid was filtered and dried to afford 11.1 g of gemcitabine free base. 0.5N HCl (240 ml) was added followed by addition of dichloromethane (100 ml) with stirring. The water phase was separated and the aqueous phase was washed with dichloromethane (300 ml). After filtration, the aqueous phase was concentrated to dryness under reduced pressure to obtain gemcitabine hydrochloride as a solid (12.0 g). The solid was dissolved in water (48 ml) at ambient temperature and the mixture was heated to 5O⁰C to afford a clear solution and cooled to ambient temperature. Acetone (360 ml) was added and stirring was maintained for about one hour. Then, the precipitate was collected by filtration and washed twice with acetone (2X30 ml) and dried at 45⁰C under vacuum to obtain 9.9 g of gemcitabine hydrochloride, containing 99.6% of the β-anomer.

EXAMPLE 6

[0055] This example demonstrates the slurrying procedure of the 3 ‘,5′- dicinnamoyl-2′-deoxy-2’,2^l-difluorocytidine in different solvents. [0056] 1 g of the crude 3′,5′-dicinnamoyl-2′-deoxy-2^l,2′-difluorocytidine, containing 73.7 % of the β-anomer and 17.5 % of the α-anomer, was placed in flask and 10 ml of a solvent was added and the mixture was mixed at ambient temperature for one hour. Then, the solid was obtained by filtration, washed with 5 ml of the solvent and dried. The liquid obtained after filtering the solid and the liquid obtained after washing the solid were combined (hereinafter the mother liquor). The ratio between the β-anomer and the α-anomer in the solid and in the mother liquor was determined by HPLC and the results are summarized in Table 1.

Table 1

/////////

AS ON DEC2021 3,491,869 VIEWS ON BLOG WORLDREACH AVAILABLEFOR YOUR ADVERTISEMENT

join me on Linkedin

Anthony Melvin Crasto Ph.D – India | LinkedIn

join me on Researchgate

RESEARCHGATE

join me on Facebook

Anthony Melvin Crasto Dr. | Facebook

• Twitter
• FACEBOOK

join me on twitter

Anthony Melvin Crasto Dr. | twitter

+919321316780 call whatsaapp

EMAIL. amcrasto@amcrasto

/////////////////////////////////////////////////////////////////////////////

Adverse effects

Gemcitabine is a chemotherapy drug that works by killing any cells that are dividing.^[10] Cancer cells divide rapidly and so are targeted at higher rates by gemcitabine, but many essential cells also divide rapidly, including cells in skin, the scalp, the stomach lining, and bone marrow, resulting in adverse effects.^[16]: 265

The gemcitabine label carries warnings that it can suppress bone marrow function and cause loss of white blood cells, loss of platelets, and loss of red blood cells, and that it should be used carefully in people with liver, kidney, or cardiovascular disorders. People taking it should not take live vaccines. The warning label also states it may cause posterior reversible encephalopathy syndrome, that it may cause capillary leak syndrome, that it may cause severe lung conditions like pulmonary edema, pneumonia, and adult respiratory distress syndrome, and that it may harm sperm.^[10][17]

More than 10% of users develop adverse effects, including difficulty breathing, low white and red blood cells counts, low platelet counts, vomiting and nausea, elevated transaminases, rashes and itchy skin, hair loss, blood and protein in urine, flu-like symptoms, and edema.^[10][15]

Common adverse effects (occurring in 1–10% of users) include fever, loss of appetite, headache, difficulty sleeping, tiredness, cough, runny nose, diarrhea, mouth and lip sores, sweating, back pain, and muscle pain.^[10]

Thrombotic thrombocytopenic purpura (TTP) is a rare but serious side effect that been associated with particular chemotherapy medications including gemcitabine. TTP is a blood disorder and can lead to microangipathic hemolytic anemia (MAHA), neurologic abnormalities, fever, and renal disease.^[18]

Pharmacology

Gemcitabine is hydrophilic and must be transported into cells via molecular transporters for nucleosides (the most common transporters for gemcitabine are SLC29A1 SLC28A1, and SLC28A3).^[19][20] After entering the cell, gemcitabine is first modified by attaching a phosphate to it, and so it becomes gemcitabine monophosphate (dFdCMP).^[19][20] This is the rate-determining step that is catalyzed by the enzyme deoxycytidine kinase (DCK).^[19][20] Two more phosphates are added by other enzymes. After the attachment of the three phosphates gemcitabine is finally pharmacologically active as gemcitabine triphosphate (dFdCTP).^[19] [21]

After being thrice phosphorylated, gemcitabine can masquerade as deoxycytidine triphosphate and is incorporated into new DNA strands being synthesized as the cell replicates.^[2][19][20]

When gemcitabine is incorporated into DNA it allows a native, or normal, nucleoside base to be added next to it. This leads to “masked chain termination” because gemcitabine is a “faulty” base, but due to its neighboring native nucleoside it eludes the cell’s normal repair system (base-excision repair). Thus, incorporation of gemcitabine into the cell’s DNA creates an irreparable error that leads to inhibition of further DNA synthesis, and thereby leading to cell death.^[2][19][20]

The form of gemcitabine with two phosphates attached (dFdCDP) also has activity; it inhibits the enzyme ribonucleotide reductase (RNR), which is needed to create new DNA nucleotides. The lack of nucleotides drives the cell to uptake more of the components it needs to make nucleotides from outside the cell, which also increases uptake of gemcitabine.^{[2][19][20][22]}

Chemistry

Gemcitabine is a synthetic pyrimidine nucleoside prodrug—a nucleoside analog in which the hydrogen atoms on the 2′ carbon of deoxycytidine are replaced by fluorine atoms.^[2][23][24]

The synthesis described and pictured below is the original synthesis done in the Eli Lilly Company labs. Synthesis begins with enantiopure D-glyceraldehyde (R)-2 as the starting material which can made from D-mannitol in 2–7 steps. Then fluorine is introduced by a “building block” approach using ethyl bromodifluroacetate. Then, Reformatsky reaction under standard conditions will yield a 3:1 anti/syn diastereomeric mixture, with one major product. Separation of the diastereomers is carried out via HPLC, thus yielding the anti-3 gemcitabine in a 65% yield.^[23][24] At least two other full synthesis methods have also been developed by different groups.^[24]

History[

Gemcitabine was first synthesized in Larry Hertel’s lab at Eli Lilly and Company during the early 1980s. It was intended as an antiviral drug, but preclinical testing showed that it killed leukemia cells in vitro.^[25]

During the early 1990s gemcitabine was studied in clinical trials. The pancreatic cancer trials found that gemcitabine increased one-year survival time significantly, and it was approved in the UK in 1995^[10] and approved by the FDA in 1996 for pancreatic cancers.^[4] In 1998, gemcitabine received FDA approval for treating non-small cell lung cancer and in 2004, it was approved for metastatic breast cancer.^[4]

European labels were harmonized by the EMA in 2008.^[26]

By 2008, Lilly’s worldwide sales of gemcitabine were about $1.7 billion; at that time its US patents were set to expire in 2013 and its European patents in 2009.^[27] The first generic launched in Europe in 2009,^[7] and patent challenges were mounted in the US which led to invalidation of a key Lilly patent on its method to make the drug.^[28][29] Generic companies started selling the drug in the US in 2010 when the patent on the chemical itself expired.^[29][8] Patent litigation in China made headlines there and was resolved in 2010.^[30]

Society and culture

As of 2017, gemcitabine was marketed under many brand names worldwide: Abine, Accogem, Acytabin, Antoril, axigem, Bendacitabin, Biogem, Boligem, Celzar, Citegin, Cytigem, Cytogem, Daplax, DBL, Demozar, Dercin, Emcitab, Enekamub, Eriogem, Fotinex, Gebina, Gemalata, Gembin, Gembine, Gembio, Gemcel, Gemcetin, Gemcibine, Gemcikal, Gemcipen, Gemcired, Gemcirena, Gemcit, Gemcitabin, Gemcitabina, Gemcitabine, Gemcitabinum, Gemcitan, Gemedac, Gemflor, Gemful, Gemita, Gemko, Gemliquid, Gemmis, Gemnil, Gempower, Gemsol, Gemstad, Gemstada, Gemtabine, Gemtavis, Gemtaz, Gemtero, Gemtra, Gemtro, Gemvic, Gemxit, Gemzar, Gentabim, Genuten, Genvir, Geroam, Gestredos, Getanosan, Getmisi, Gezt, Gitrabin, Gramagen, Haxanit, Jemta, Kalbezar, Medigem, Meditabine, Nabigem, Nallian, Oncogem, Oncoril, Pamigeno, Ribozar, Santabin, Sitagem, Symtabin, Yu Jie, Ze Fei, and Zefei.^[1]

Research

Because it is clinically valuable and is only useful when delivered intravenously, methods to reformulate it so that it can be given by mouth have been a subject of research.^[31][32][33]

Research into pharmacogenomics and pharmacogenetics has been ongoing. As of 2014, it was not clear whether or not genetic tests could be useful in guiding dosing and which people respond best to gemcitabine.^[19] However, it appears that variation in the expression of proteins (SLC29A1, SLC29A2, SLC28A1, and SLC28A3) used for transport of gemcitabine into the cell lead to variations in its potency. Similarly, the genes that express proteins that lead to its inactivation (deoxycytidine deaminase, cytidine deaminase, and NT5C) and that express its other intracellular targets (RRM1, RRM2, and RRM2B) lead to variations in response to the drug.^[19] Research has also been ongoing to understand how mutations in pancreatic cancers themselves determine response to gemcitabine.^[34]

It has been studied as a treatment for Kaposi sarcoma, a common cancer in people with AIDS which is uncommon in the developed world but not uncommon in the developing world.^[35]

References

External links

• “Gemcitabine”. Drug Information Portal. U.S. National Library of Medicine.

Gemcitabine

Clinical data
Pronunciation	/dʒɛmˈsaɪtəbiːn/
Trade names	Gemzar, others[1]
Other names	2′, 2′-difluoro 2’deoxycytidine, dFdC
AHFS/Drugs.com	Monograph
Pregnancy category	AU: D
Routes of administration	Intravenous
ATC code	L01BC05 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) UK: POM (Prescription only) US: ℞-only In general: ℞ (Prescription only)
Pharmacokinetic data
Protein binding	<10%
Elimination half-life	Short infusions: 32–94 minutes Long infusions: 245–638 minutes
Identifiers
show IUPAC name
CAS Number	95058-81-4
PubChem CID	60750
IUPHAR/BPS	4793
DrugBank	DB00441
ChemSpider	54753
UNII	B76N6SBZ8R
KEGG	D02368
ChEBI	CHEBI:175901
ChEMBL	ChEMBL888
CompTox Dashboard (EPA)	DTXSID3040487
ECHA InfoCard	100.124.343
Chemical and physical data
Formula	C9H11F2N3O4
Molar mass	263.201 g·mol−1
3D model (JSmol)	Interactive image
show SMILES
show InChI
(verify)

/////////////GEMCITABINE, LY 188011, LY188011, CANCER

NC1=NC(=O)N(C=C1)[C@@H]1O[C@H](CO)[C@@H](O)C1(F)F

Patent