95058-81-4

Usage

Uses

Used in Oncology:
Gemcitabine is used as an anticancer agent for the treatment of various types of cancer, including breast cancer, ovarian cancer, pancreatic cancer, lung cancer, bladder cancer, bone cancer, Ewing's sarcoma, mesenchymal chondrosarcoma, osteosarcoma, dedifferentiated chondrosarcoma, head and neck cancers, hepatobiliary cancers, Hodgkin lymphoma, kidney cancer, malignant pleural mesothelioma, non-Hodgkin lymphoma, non-melanoma skin cancer, small cell lung cancer, soft tissue sarcoma, testicular cancer, thymic malignancies, and uterine malignancies.
Used in Combination Therapy:
Gemcitabine is used in combination with other medicines to enhance the treatment of cancer. It is particularly effective as a first-line treatment for locally advanced pancreatic cancer and has shown synergistic effects when combined with conventional chemotherapeutic drugs, improving chemo-sensitivity and efficacy in resistant cases.
Used in Radiosensitization:
Gemcitabine is used as a potent radiosensitizer, increasing the cytotoxicity of other chemotherapeutic agents such as cisplatin. This property makes it useful in combination therapies to improve the effectiveness of radiation treatments.
Used in Antiviral Applications:
Gemcitabine has demonstrated broad antiretroviral activity, decreasing cell infectivity in murine AIDS models and inhibiting the progression of the disease in vivo. This suggests potential applications in the treatment of retroviral infections.
Gemcitabine is available as the hydrochloride salt in lyophilized single-dose vials for intravenous use. It is metabolized to its active forms within cells, where it inhibits DNA synthesis and function, leading to cell death. However, resistance to Gemcitabine can occur due to decreased expression of activation enzymes, decreased drug transport, or increased expression of catabolic enzymes. The drug has low oral bioavailability due to deamination within the gastrointestinal tract and does not cross the blood-brain barrier. Common side effects of Gemcitabine treatment include myelosuppression, fever, malaise, chills, headache, myalgias, nausea, and vomiting.

References

[1] H. A. Burris, M. J. Moore, J. Andersen, M. R. Green, M. L. Rothenberg, M. R. Modiano, M. C. Cripps, R. K. Portenoy, A. M. Storniolo, P. Tarassoff, R. Nelson, F. A. Dorr, C. D. Stephens, D. D. Von Hoff (1997) Improvements in survival and clinical benefit with gemcitabine as first-line therapy for patients with advanced pancreas cancer: a randomized trial, 15, 2403-2413 [2] http://www.webmd.com/drugs/2/drug-13451/gemcitabine-intravenous/details

Originator

Gemzar,Lilly Co.

Indications

Gemcitabine (Gemzar), an antimetabolite, undergoes metabolic activation to difluorodeoxycytidine triphosphate, which interferes with DNA synthesis and repair. It is the single most active agent for the treatment of metastatic pancreatic cancer, and it is used as a first-line treatment for both pancreatic and small cell lung cancer. It is administered by intravenous infusion. The dose-limiting toxicity is bone marrow suppression.

Manufacturing Process

Benzyl 4,6-O-benzylidene-2-O-benzyl-3-oxo-α-D-gluco-pyranoside was obtained by 4 steps from glucose. 0.53 ml (4.0 mmol) of DAST (fluorinaiting agent) was added to asolution of 300 mg (0.67 mmol) of benzyl 4,6-O-benzylidene-2-O-benzyl-3-oxo-α-Dgluco-pyranoside in anhydrous dichloromethane (4 ml). The solution was then stirred at room temperature for 2 h, and the excess of DAST was neutralized by careful addition of saturated aqueous NaHCO3. The resulting mixture was extracted with CH2Cl2, and organic phase was dried and evaporated. The residue was purified by CC (Hexane/Ethyl acetate 7:1) to afford benzyl 4,6-Obenzylidene-2-O-benzyl-3-deoxy-3,3-difluoro-α-D-gluco-pyranoside (189 mg, 60%), melting point 118°-119°C. Benzyl 4,6-O-benzylidene-2-O-benzyl-3-deoxy-3,3-difluoro-α-D-glucopyranoside (77 mg, 0.16 mmol) was dissolved in a 0.1 N solution of HCl in ethanol and stirred at room temperature for 40 h. The solution was then neutralized with solid NaHCO3, filtered and evaporated to give an oily product that was dissolved in 2 ml of CH2Cl2 and 0.5 ml of pyridine. After cooling to 0°C, 0.40 ml (1.6 mmol) of benzoyl chloride was added and the solution was stirred for 1 h and poured into ice and water (200 ml) containing NaHCO3, extracted several times with CH2Cl2, dried and evaporated to give 86 mg (0.14 mmol, 90%) of benzyl 4,6-di-O-benzoyl-2-O-benzyl-3-deoxy-3,3- difluoro-α-D-gluco-pyranoside. Benzyl 4,6-di-O-benzoyl-2-O-benzyl-3-deoxy-3,3-difluoro-α-D-glucopyranoside (220 mg, 0.44 mmol) was dissolved in methanol in the presence of 200 mg of palladium on activated charcoal (10% Pd content). The suspension was stirred at room temperature under hydrogen pressure (10 bar) for 16 h. The suspension was then filtered through a thin silica gel pad, and evaporated. The residue was purified by CC to give 105 mg (59%) of 4,6- di-O-benzoyl-3-deoxy-3,3-difluoro-α/β-D-gluco-pyranoside as an inseparable anomeric mixture (ratio α/β = 5:1). To a solution of 46 mg (0.11 mmol) of 4,6-di-O-benzoyl-3-deoxy-3,3-difluoro- α/β-D-gluco-pyranoside in water-dioxane 1:2 (2 ml) was added 120 mg (0.56 mmol) of sodium periodate. This resulting solution was stirred at room temperature for 20 h. Then, more sodium periodate (55 mg, 0.26 mmol) was added and stirring was continued for 6 h. After that, the solvents were evaporated and the solid was repeatedly extracted with ethyl acetate (total volume 70 ml). The solvent was then evaporated to give a solid that was treated for 15 min with a diluted (0.1%) methanolic solution of ammonia. THE solution was evaporated and the crude purified by preparative TLC (hexane/ethyl acetate 2:1) to yield 18 mg (0.04 mmol, 43%) of α-3,5-di-Obenzoyl-2-deoxy-2,2-difluoro-D-ribose.

Hazard

Human systemic effects

Clinical Use

Antineoplastic agent: Palliative treatment, or first-line treatment with cisplatin, of locally advanced or metastatic non-small cell lung cancer Pancreatic, ovarian and breast cancer Bladder cancer in combination with cisplatin

Drug interactions

Potentially hazardous interactions with other drugs Antipsychotics: avoid with clozapine, increased risk of agranulocytosis.

Metabolism

After intravenous doses gemcitabine is rapidly cleared from the blood and metabolised by cytidine deaminase in the liver, kidney, blood, and other tissues. Clearance is about 25% lower in women than in men. Almost all (99%) of the dose is excreted in urine as 2′-deoxy-2′,2′-difluorouridine (dFdU), only about 1% being found in the faeces. Intracellular metabolism produces mono-, di-, and triphosphate metabolites, the latter two active. The active intracellular metabolites have not been detected in plasma or urine.

references

[1] karnitz lm, flatten ks, wagner jm, et al. gemcitabine-induced activation of checkpoint signaling pathways that affect tumor cell survival. mol pharmacol, 2005, 68 (6): 1636-1644. [2] ando t, ichikawa j, okamoto a, et al. gemcitabine inhibits viability, growth, and metastasis of osteosarcoma cell lines. j orthop res, 2005, 23 (4): 964-969. [3] clouser cl, holtz cm, mullett m, et al. analysis of the ex vivo and in vivo antiretroviral activity of gemcitabine. plos one, 2011, 6 (1): e15840.

InChI:InChI=1/C9H11F2N3O4/c10-9(11)6(16)4(3-15)18-7(9)14-2-1-5(12)13-8(14)17/h1-2,4,6-7,15-16H,3H2,(H2,12,13,17)/t4-,6-,7?/m1/s1

Synthetic route

(2R,3R,5R)-5-(4-amino-2-oxopyrimidine-1(2H)-yl)-4,4-difluoro-2-((3-fluorobenzoyloxy)methyl)tetrahydrofuran-3-yl 3-fluorobenzoate (942288-40-6) → gemcitabine (95058-81-4)

Conditions	Yield
With ammonia; water at 20℃; for 3h;	100%
With methanol; ammonia; water at 20℃; for 3h;	100%

(2'-deoxy-2',2'-difluorocytidine)-3',5'-dibenzoate (134790-39-9) → gemcitabine (95058-81-4)

Conditions	Yield
With ammonium hydroxide In methanol at 20℃; for 3h;	82.7%
With sodium t-butanolate In methanol at 20℃; for 2h;

1-(2'-deoxy-2',2'-difluoro-5-benzoyl-3-(4-phenyl)benzoyl-β-D-arabinofuranosyl)-4-aminopyrimidine-2-one (896109-84-5) → gemcitabine (95058-81-4)

Conditions	Yield
With ammonia In methanol at 20℃; for 12h; Product distribution / selectivity;	76.9%

1-(5'-O-benzoyl-2'-deoxy-2',2'-difluoro-3-O-(p-phenylbenzoyl)-D-ribofuranosyl)-4-aminopyrimidin-2-one → gemcitabine (95058-81-4)

Conditions	Yield
With ammonia In methanol at 20℃; Product distribution / selectivity;	72.6%
With ammonia In methanol at 20℃; Product distribution / selectivity;	72.6%
With ammonia; water In methanol at 20℃; for 12h;	71%
With ammonia In methanol at 20℃; Product distribution / selectivity;

(2R,3R)-5-(4-acetamido-2-oxopyrimidin-1(2H)-yl)-2-((benzoyloxy)methyl)-4,4-difluorotetrahydrofuran-3-yl benzoate → gemcitabine (95058-81-4)

Conditions	Yield
With Amberlite IRA 400, OH-form In methanol at 40 - 45℃; for 36h; Product distribution / selectivity;	71%
With ammonia In methanol; water at 20℃; for 24h; Product distribution / selectivity;

C31H25F2N3O7 → gemcitabine (95058-81-4)

Conditions	Yield
With ammonia In methanol Product distribution / selectivity;	63%
With ammonia In methanol for 8h; Product distribution / selectivity;	63%
With ammonia In methanol

2-amino-N-(1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-2-oxo-1,2-dihydropyrimidin-4-yl)acetamide trifluoroacetic acid (1018907-93-1) → C11H14F2N4O5 (1018908-06-9) + gemcitabine (95058-81-4)

Conditions	Yield
With sodium hydrogencarbonate In methanol	A 51% B n/a

2'-deoxy-2',2'-difluoro-3',5'-di-O-(triisopropylsilyl)cytidine (1260238-57-0) → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
With tetramethylammonium fluoride; acetic acid In N,N-dimethyl-formamide at 20℃; stereoselective reaction;	A 42% B 36%
With tetramethylammonium fluoride; acetic acid In N,N-dimethyl-formamide at 20℃;

C2HF3O2*C14H18F2N4O5 (1018908-14-9) → C14H18F2N4O5 (1018908-15-0) + gemcitabine (95058-81-4)

Conditions	Yield
With sodium hydrogencarbonate In methanol	A 38% B n/a

bis(trimethylsilyl)-N-acetylcytosine (18027-23-1) + 3,5-bis-O-(tert-butyldimethylsilyl)-1-O-(methanesulfonyl)-2-deoxy-2,2-difluororibose (103882-89-9) → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
Multistep reaction;

1-[2'-deoxy-2',2'-difluoro-3',5'-bis(tert-butyldiphenylsilyloxy)-ribofuranosyl]-cytosine (952408-92-3) → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
With ammonium fluoride In methanol at 65℃; for 3h;

gemcitabine hydrochloride (122111-03-9) → gemcitabine (95058-81-4)

Conditions	Yield
With potassium carbonate In ethanol; dichloromethane at 20℃;
With triethylamine In N,N-dimethyl-formamide at 20℃; for 0.0833333h;
Multi-step reaction with 4 steps 1: 1H-imidazole / N,N-dimethyl-formamide / 2.5 h / 20 °C 2: pyridine / tetrahydrofuran / 1 h / 4 °C 3: tetrabutyl ammonium fluoride / tetrahydrofuran / 20 °C 4: Pd0-functionalized resin / aq. phosphate buffer / 37 °C / pH 7.4 View Scheme
Multi-step reaction with 4 steps 1: 1H-imidazole / N,N-dimethyl-formamide / 2.5 h / 20 °C 2: pyridine / tetrahydrofuran / 20 °C 3: tetrabutyl ammonium fluoride / tetrahydrofuran / 20 °C 4: Pd0-functionalized resin / aq. phosphate buffer / 37 °C / pH 7.4 View Scheme
Multi-step reaction with 4 steps 1: 1H-imidazole / N,N-dimethyl-formamide / 2.5 h / 20 °C 2: pyridine / tetrahydrofuran / 48 h / 20 °C 3: tetrabutyl ammonium fluoride / tetrahydrofuran / 3 h / 20 °C 4: Pd0-functionalized resin / aq. phosphate buffer / 37 °C / pH 7.4 View Scheme

N4-benzoyl-2'-deoxy-2',2'-difluorocytidine (142816-70-4) → gemcitabine (95058-81-4)

Conditions	Yield
With pyridine; ammonium hydroxide In water at 37℃; for 18h; Kinetics;

C13H15F2N3O6 (861445-90-1) → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
With sodium ethanolate In isopropyl alcohol for 1 - 6h; Heating / reflux;

N-(1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-2-oxo-1,2-dihydropyrimidin-4-yl)-2-propylpentanamide (892128-60-8) → gemcitabine (95058-81-4)

Conditions	Yield
With water; CD-1 mouse small intestinal homogenate for 6h; pH=7.5; Conversion of starting material; Aqueous acetate buffer; Enzymatic reaction;
With water; CD-1 mouse post-mitochondrial liver (S9) homogenate for 6h; pH=8.0; Conversion of starting material; Aqueous phosphate buffer; Enzymatic reaction;
With water; beagle dog post-mitochondrial liver (S9) homogenate for 6h; pH=8.0; Conversion of starting material; Aqueous phosphate buffer; Enzymatic reaction;

1-(5'-O-benzoyl-2'-deoxy-2',2'-difluoro-3-O-(p-phenylbenzoyl)-D-ribofuranosyl)-4-aminopyrimidin-2-one → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
With ammonia In methanol at 20℃; Product distribution / selectivity;
With ammonia In methanol at 20℃;
With ammonia In methanol at 20℃; for 10h; Product distribution / selectivity;

N4-(1-(5-nitrothien-2-yl)ethyl)oxycarbonyl-2',2'-difluoro-2'-deoxycytidine → gemcitabine (95058-81-4)

Conditions	Yield
In water; isopropyl alcohol G-values; Irradiation;

N4-(2-nitro-1-methylimidazol-5-yl)methoxycarbonyl-2',2'-difluoro-2'-deoxycytidine → gemcitabine (95058-81-4)

Conditions	Yield
In water; isopropyl alcohol G-values; Irradiation;

N4-(5-nitrothien-2-yl)methoxycarbonyl-2',2'-difluoro-2'-deoxycytidine → gemcitabine (95058-81-4)

Conditions	Yield
In water; isopropyl alcohol G-values; Irradiation;

3',5'-bis(tert-butyldiphenylsilyloxy)-2',2'-difluoro-2'-deoxycytidine → gemcitabine (95058-81-4)

Conditions	Yield
With tetrabutyl ammonium fluoride In tetrahydrofuran at 15 - 30℃; for 5.33333h;

2',2'-difluoro-2'-deoxy-N-acetylcytidine-3',5'-dibenzoate → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
With methanol; ammonia at -5 - 5℃; for 8 - 10h;

(2R,3R,5R)-5-(4-amino-2-oxopyrimidin-1(2H)-yl)-4,4-difluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl benzoate hydrochloride (1147119-18-3) → gemcitabine (95058-81-4)

Conditions	Yield
With ammonia In methanol Product distribution / selectivity;
With methanol; 2,2,2-trifluoroethanol; potassium carbonate Product distribution / selectivity;

2’-deoxy-2’,2’-difluoro-cytidine (103882-84-4) → gemcitabine (95058-81-4)

Conditions	Yield
With ammonia In water Resolution of racemate;

C23H19F2N3O6 (1155863-81-2) → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
With sodium methylate

2-deoxy-2,2-difluoro-3,5-di-O-(triisopropylsilyl)-D-ribofuranose → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: triethylamine / dichloromethane / 3 h / 0 - 20 °C / Inert atmosphere 2.1: trimethylsilyl trifluoromethanesulfonate / 1,2-dichloro-ethane / 0.5 h / 20 °C 2.2: Reflux 3.1: tetramethylammonium fluoride; acetic acid / N,N-dimethyl-formamide / 20 °C View Scheme
Multi-step reaction with 3 steps 1.1: methanesulfonyl chloride; triethylamine / dichloromethane 2.1: trimethylsilyl trifluoromethanesulfonate / 1,2-dichloro-ethane / 0.5 h / 20 °C 2.2: Reflux 3.1: tetramethylammonium fluoride; acetic acid / N,N-dimethyl-formamide / 20 °C View Scheme

1-methylsulfonyl-2-deoxy-2,2-difluoro-3,5-di-O-(triisopropylsilyl)-D-ribofuranose (1173700-36-1) → α-1-(2-oxo-4-amino-1,2-dihydropyrimidin-1-yl)-2-deoxy-2,2-difluororibose (95058-85-8) + gemcitabine (95058-81-4)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: trimethylsilyl trifluoromethanesulfonate / 1,2-dichloro-ethane / 0.5 h / 20 °C 1.2: Reflux 2.1: tetramethylammonium fluoride; acetic acid / N,N-dimethyl-formamide / 20 °C View Scheme
Multi-step reaction with 2 steps 1.1: trimethylsilyl trifluoromethanesulfonate / 1,2-dichloro-ethane / 0.5 h / 20 °C 1.2: Reflux 2.1: tetramethylammonium fluoride; acetic acid / N,N-dimethyl-formamide / 20 °C View Scheme

C4H11N*C9H11F2N3O4*C72H72N4O12*H(1+) → C4H11N*C72H72N4O12*H(1+) + gemcitabine (95058-81-4)

Conditions	Yield
at 20℃; under 9.0009E-09 Torr; Kinetics; Fourier-Transform Ion Cyclotron Resonance mass spectrometer;

C4H11N*C9H11F2N3O4*C72H72N4O12*H(1+) → C4H11N*C72H72N4O12*H(1+) + gemcitabine (95058-81-4)

Conditions	Yield
at 20℃; under 9.75098E-09 Torr; Kinetics; Fourier-Transform Ion Cyclotron Resonance mass spectrometer;

C4H11N*C9H11F2N3O4*C72H72N4O12*H(1+) → C4H11N*C72H72N4O12*H(1+) + gemcitabine (95058-81-4)

Conditions	Yield
at 20℃; under 3.0003E-08 Torr; Kinetics; Fourier-Transform Ion Cyclotron Resonance mass spectrometer;

1,3-Dichloro-1,1,3,3-tetraisopropyldisiloxane (69304-37-6) + gemcitabine (95058-81-4) → 4-amino-1-((6aR,8R,9aR)-9,9-difluoro-2,2,4,4-tetraisopropyltetrahydro-6H-furo[3,2-f] [1,3,5,2,4]trioxadisilocin-8-yl)pyrimidin-2(1H)-one (1254062-21-9)

Conditions	Yield
With pyridine at 20℃; for 4h;	100%
With pyridine at 20℃; for 48h;	84%
With 1H-imidazole In N,N-dimethyl-formamide at 20℃; for 16h; Inert atmosphere;	82.3%

tert-butyldimethylsilyl chloride (18162-48-6) + gemcitabine (95058-81-4) → 4-amino-1-((2R,4R,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(((tert-butyldimethylsilyl)oxy)methyl)-3,3-difluoro-tetrahydrofuran-2-yl)pyrimidin-2(1H)-one (688009-09-8)

Conditions	Yield
With 1H-imidazole In N,N-dimethyl-formamide at 20℃; Cooling with ice; Inert atmosphere;	99%
With 1H-imidazole at 20℃;	97.1%
With 1H-imidazole In N,N-dimethyl-formamide at 20℃; Solvent; Reagent/catalyst;	95%

chloroformic acid ethyl ester (541-41-3) + gemcitabine (95058-81-4) → 1-[(2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)oxolan-2-yl]-1,2-dihydro-4-(ethoxycarbonylamino)pyrimidin-2-one (155968-14-2)

Conditions	Yield
In ethyl acetate; acetonitrile for 3h; Inert atmosphere; Reflux;	98.31%

di-tert-butyl dicarbonate (24424-99-5) + gemcitabine (95058-81-4) → (2R,3R,5R)-5-(4-amino-2-oxopyrimidin-1(2H)-yl)-4,4-difluoro-2-(hydroxymethyl)tetrahydrofuran-3-yl tert-butyl carbonate (250698-51-2)

Conditions	Yield
With sodium carbonate In 1,4-dioxane; water at 20℃; for 50h;	94%
With sodium carbonate In water at 20℃; for 30h;	89%
With sodium carbonate In 1,4-dioxane; water at 20℃; for 72h;	88%

1,5-pentanedioic acid (110-94-1) + gemcitabine (95058-81-4) + 1-hydroxybenzotriazol-hydrate (80029-43-2, 123333-53-9) → 5-((1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl)-2-oxo-1,2-dihydro-pyrimidin-4-yl)amino)-5-oxo-pentanoic acid

Conditions	Yield
With 4-methyl-morpholine	94%

gemcitabine (95058-81-4) → gemcitabine hydrochloride (122111-03-9)

Conditions	Yield
With hydrogenchloride In water; isopropyl alcohol at 20 - 70℃;	93.4%
With hydrogenchloride In water; acetone at 20℃; for 2h; Product distribution / selectivity;	91.5%
With hydrogenchloride In isopropyl alcohol at 0 - 5℃; for 2h; pH=2;	90%

di-tert-butyl dicarbonate (24424-99-5) + gemcitabine (95058-81-4) → 3′,5′-O-bis(tert-butoxycarbonyl)-gemcitabine (250698-52-3)

Conditions	Yield
Stage #1: gemcitabine With potassium hydroxide In water at 20℃; for 1h; Stage #2: di-tert-butyl dicarbonate In 1,4-dioxane; water at 20℃; for 1h;	93%
Stage #1: gemcitabine With potassium hydroxide In water for 1h; Stage #2: di-tert-butyl dicarbonate In 1,4-dioxane; water at 20℃; for 2.67h;	90%
With potassium hydroxide In 1,4-dioxane

benzoyl chloride (98-88-4) + gemcitabine (95058-81-4) → (2R,3R,5R)-5-(4-benzamido-2-oxopyrimidin-1(2H)-yl)-2-((benzoyloxy)methyl)-4,4-difluorotetrahydrofuran-3-yl benzoate (1445381-44-1)

Conditions	Yield
With pyridine; dmap at 0 - 20℃; for 3.5h; Inert atmosphere;	93%

trityl chloride (76-83-5) + gemcitabine (95058-81-4) → 5'-Tr-gemcytabine

Conditions	Yield
With triethylamine In pyridine at 20℃; for 6h; Inert atmosphere; Cooling with ice; regioselective reaction;	91.2%

Azelaic anhydride (45289-91-6) + gemcitabine (95058-81-4) → 5-((1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl)-2-oxo-1,2-dihydro-pyrimidin-4-yl)amino)-5-oxo-nonanoic acid

Conditions	Yield
	91%

benzyl chloroformate (501-53-1) + gemcitabine (95058-81-4) → 4-(benzyloxycarbonylamino)-1-(2-deoxy-2,2-difluoro-β-D-erythro-pentofuranosyl)pyrimidin-2(1H)-one (138685-83-3)

Conditions	Yield
Stage #1: gemcitabine With pyridine; chloro-trimethyl-silane at 4 - 20℃; for 1.5h; Inert atmosphere; Stage #2: benzyl chloroformate In methanol at 20℃; Inert atmosphere;	91%

gemcitabine (95058-81-4) → 4-amino-1-(2-deoxy-2,2’-difluoro-β-D-erythro-pentofuranosyl)-5-iodopyrimidin-2(1H)-one (95058-82-5)

Conditions	Yield
With hydrogen iodide; iodine In tetrachloromethane; ethanol; water at 45℃; for 16h;	90%

gemcitabine (95058-81-4) + p-toluenesulfonyl chloride (98-59-9) → N-(1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-2-oxo-1,2-dihydropyrimidin-4-yl)-4-methylbenzenesulfonamide (1519060-68-4)

Conditions	Yield
With pyridine; chloro-trimethyl-silane; ammonia In methanol Inert atmosphere;	90%
With pyridine; chloro-trimethyl-silane at 20℃; for 2h; Inert atmosphere;	83%

vinyl myristate (5809-91-6) + gemcitabine (95058-81-4) → O5’-tetradecanoyl-2',2'-difluoro-2'-deoxycytidine

Conditions	Yield
With pyridine; lipase B Candida antarctica In hexane at 50℃; for 6h; Enzymatic reaction;	89%

N-(pyridin-4-carbonyl)-D-Ala-L-Proline + gemcitabine (95058-81-4) → C23H26F2N6O7

Conditions	Yield
With N-ethyl-N,N-diisopropylamine; HATU In N,N-dimethyl-formamide	87%

di-tert-butyl dicarbonate (24424-99-5) + gemcitabine (95058-81-4) → tert-butyl [1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-hydroxymethyl-tetrahydrofuran-2-yl)-2-oxo-1,2-dihydro-pyrimidin-4-yl]-carbamate

Conditions	Yield
In N,N-dimethyl-formamide at 50℃; for 18h;	86%
In N,N-dimethyl-formamide at 50℃; for 18h;	86%

(R)-2-((R)-(2,3,4,5,6-pentafluorophenoxy)phenoxyphosphorylamino)propionic acid isopropyl ester + gemcitabine (95058-81-4) → C21H27F2N4O8P

Conditions	Yield
In tetrahydrofuran at 0℃;	85%

(S)-2-[((S)-(2,3,4,5,6-pentafluorophenoxy)(phenoxy)phosphoryl)amino]propionic acid isopropyl ester (1334513-02-8) + gemcitabine (95058-81-4) → isopropyl ((S)-(((2R,3R,5R)-5-(4-amino-2-oxopyrimidin-1(2H)-yl)-4,4-difluoro-3-hydroxytetrahydrofuran-2-yl)methoxy)(phenoxy)phosphoryl)-L-alaninate

Conditions	Yield
With pyridine; dimethylaluminum chloride In hexane at 0 - 20℃; for 22h; Inert atmosphere; diastereoselective reaction;	83%

(fluorenylmethoxy)carbonyl chloride (28920-43-6) + gemcitabine (95058-81-4) → (9H-fluoren-9-yl)methyl (1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)-tetrahydrofuran-2-yl)-2-oxo-1,2-dihydropyrimidin-4-yl)carbamate

Conditions	Yield
Stage #1: gemcitabine With pyridine; chloro-trimethyl-silane for 0.333333h; Stage #2: (fluorenylmethoxy)carbonyl chloride In water for 2.5h;	80.9%
Stage #1: gemcitabine With 1H-imidazole; dmap; tert-butyldimethylsilyl chloride In N,N-dimethyl-formamide at 20℃; Stage #2: (fluorenylmethoxy)carbonyl chloride With pyridine In dichloromethane at 20℃; Stage #3: With pyridine hydrogenfluoride In tetrahydrofuran at 20℃; for 24h;	79.4%

4,4'-dimethoxytrityl chloride (40615-36-9) + gemcitabine (95058-81-4) → C30H29F2N3O6 (1421929-71-6)

Conditions	Yield
With pyridine at 20℃; for 4h;	80%
With pyridine at 0 - 20℃; for 4h;	64%
With pyridine at 0 - 20℃; for 4h;	39%

(2S)-2-[(S)-(2,3,4,5,6-pentafluorophenoxy)-phenoxy-phosphorylamino]propionic acid benzyl ester + gemcitabine (95058-81-4) → benzyl ((S)-(((2R,3R,5R)-5-(4-amino-2-oxopyrimidin-1(2H)-yl)-4,4-difluoro-3-hydroxytetrahydrofuran-2-yl)methoxy)(phenoxy)phosphoryl)-L-alaninate

Conditions	Yield
With pyridine; dimethylaluminum chloride In hexane at 0 - 20℃; for 20h; Inert atmosphere; diastereoselective reaction;	80%

C18H26O13 (807370-86-1) + gemcitabine (95058-81-4) → C27H35F2N3O16

Conditions	Yield
Stage #1: C18H26O13 With 1-hydroxy-pyrrolidine-2,5-dione; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In N,N-dimethyl-formamide at 20℃; for 2h; Inert atmosphere; Stage #2: gemcitabine In N,N-dimethyl-formamide at 20℃; for 24h; Inert atmosphere;	80%

gemcitabine (95058-81-4) → Gemcitabine monophosphate (116371-67-6)

Conditions	Yield
Stage #1: gemcitabine With trichlorophosphate at 20℃; for 0.15h; Flow reactor; Green chemistry; Stage #2: With water at 20℃; Temperature; Flow reactor; Green chemistry; chemoselective reaction;	78%
With trimethyl phosphite; trichlorophosphate at -5℃; for 2h;	53%
With recombinant deoxyribonucleoside kinase AtdNK from Arabidopsis thaliana (ecotype Columbia); ATP In aq. buffer Kinetics; Concentration; Reagent/catalyst; Enzymatic reaction;
Multi-step reaction with 5 steps 1: pyridine / 4 h / 0 - 20 °C 2: pyridine / 2 h / 0 - 20 °C 3: toluene-4-sulfonic acid / dichloromethane / 2 h / 20 °C 4: 1,8-diazabicyclo[5.4.0]undec-7-ene / acetonitrile / 4 h / 20 °C 5: ammonium hydroxide View Scheme
Multi-step reaction with 7 steps 1: pyridine / 4 h / 0 - 20 °C 2: pyridine / 2 h / 0 - 20 °C 3: toluene-4-sulfonic acid / dichloromethane / 2 h / 20 °C 4: N-ethyl-N,N-diisopropylamine / dichloromethane 5: 1H-tetrazole; water / acetonitrile 6: pyridine; iodine; triethylamine; water 7: ammonium hydroxide View Scheme

vinyl laurate (2146-71-6) + gemcitabine (95058-81-4) → O5'-dodecanoyl-2',2'-difluoro-2'-deoxycytidine

Conditions	Yield
With pyridine; lipase B Candida antarctica In hexane at 50℃; for 6h; Enzymatic reaction;	76.9%

C30H33N2O8S3(1-) + gemcitabine (95058-81-4) → C39H42F2N5O11S3(1-)

Conditions	Yield
Stage #1: C30H33N2O8S3(1-) With N-ethyl-N,N-diisopropylamine In dimethyl sulfoxide at 20℃; for 0.5h; Stage #2: gemcitabine In dimethyl sulfoxide for 15h;	75%

succinic acid anhydride (108-30-5) + gemcitabine (95058-81-4) → N4-n-butyryl gemcitabine (1374587-08-2)

Conditions	Yield
With triethylamine In N,N-dimethyl-formamide at 60℃; Inert atmosphere;	75%

succinic acid (110-15-6) + gemcitabine (95058-81-4) → N-(3-Carboxy-1-oxopropyl)-2'-deoxy-2',2'-difluorocytidine

Conditions	Yield
Stage #1: succinic acid With thionyl chloride; triethylamine In 1,4-dioxane at 110℃; for 4h; Inert atmosphere; Stage #2: gemcitabine With triethylamine In N,N-dimethyl-formamide at 20℃; Inert atmosphere;	75%

Upstream product

• 1018907-93-1 2-amino-N-(1-((2R,4R,5R)-3,3-difluoro-4-hydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)-2-oxo-1,2-dihydropyrimidin-4-yl)acetamide trifluoroacetic acid 
• 1018908-14-9 C₂HF₃O₂*C₁₄H₁₈F₂N₄O₅ 
• 1173700-25-8 2-deoxy-2,2-difluoro-3,5-di-O-(triisopropylsilyl)-γ-D-ribonolactone 
• 1173700-23-6 (3S,4R,5R)-3-fluoro-4-((triisopropylsilyl)oxy)-5-(((triisopropylsilyl)oxy)methyl)-dihydrofuran-2(3H)-one 
• 34371-14-7 2-deoxy-D-ribonolactone 
• 1173824-58-2 (2R,3R)-2-((benzoyloxy)methyl)-4,4-difluoro-5-hydroxyoxolan-3-yl benzoate 
• 134877-42-2 3,5-di-O-benzoyl-2-deoxy-2,2-difluoro-1-O-methanesulfonyl-D-erythro-pentofuranose 
• 688009-09-8 4-amino-1-((2R,4R,5R)-4-((tert-butyldimethylsilyl)oxy)-5-(((tert-butyldimethylsilyl)oxy)methyl)-3,3-difluoro-tetrahydrofuran-2-yl)pyrimidin-2(1H)-one 
• 1155265-38-5 4-amino-1-((2R,4R,5R)-3,3-difluoro-4-(trimethylsilyloxy)-5-((trimethylsilyloxy)methyl)tetrahydrofuran-2-yl)pyrimidine-2(1H)-one 

Downstream Products

• 1018907-89-5 C₂₃H₂₈F₂N₄O₇ 
• 116371-67-6 Gemcitabine monophosphate 
• 1454570-55-8 gemcitabine 
• 1020657-43-5 N⁴,O-^3’-dibenzoyl-2’,2’-difluoro-2-deoxycytidine 
• 1421929-71-6 C₃₀H₂₉F₂N₃O₆ 
• 849814-02-4 C₂₃H₂₈F₂N₄O₇ 
• 688008-85-7 5'-O-L-phenylalanylgemcitabine 
• 3083-77-0 araU 

Relevant academic research and scientific papers

Combination of chemotherapy and oxidative stress to enhance cancer cell apoptosis

Cancer cells are vulnerable to reactive oxygen species (ROS) due to their abnormal redox environment. Accordingly, combination of chemotherapy and oxidative stress has gained increasing interest for the treatment of cancer. We report a novel seleno-prodrug of gemcitabine (Gem), Se-Gem, and evaluated its activation and biological effects in cancer cells. Se-Gem was prepared by introducing a 1,2-diselenolane (a five-membered cyclic diselenide) moiety into the parent drug Gemvia a carbamate linker. Se-Gem is preferably activated by glutathione (GSH) and displays a remarkably higher potency than Gem (up to a 6-fold increase) to a panel of cancer cell lines. The activation of Se-Gem by GSH releases Gem and a seleno-intermediate nearly quantitatively. Unlike the most ignored side products in prodrug activation, the seleno-intermediate further catalyzes a conversion of GSH and oxygen to GSSG (oxidized GSH) and ROS via redox cycling reactions. Thus Se-Gem may be considered as a suicide agent to deplete GSH and works by a combination of chemotherapy and oxidative stress. This is the first case that employs a cyclic diselenide in prodrug design, and the success of Se-Gem as well as its well-defined action mechanism demonstrates that the 1,2-diselenolane moiety may serve as a general scaffold to advance constructing novel therapeutic molecules with improved potency via a combination of chemotherapy and oxidative stress.

Synthesis and in vitro anticancer activity of new gemcitabine-nucleoside analogue dimers containing methyltriazole or ester-methyltriazole linker

Two series of novel gemcitabine-nucleoside analogue dimers were synthesized using the ‘click’ chemistry approach. In the first series of dimers (21–30), the nucleoside units were connected with a stable methyltriazole 4N-3′(or 5′)C linker whereas in the second series (31–40) with a cleavable ester-methyltriazole 4N-3′(or 5′)C linker. Dimers 21–40 were evaluated for their cytotoxic activity in five human cancer cell lines such as cervical (HeLa), nasopharyngeal (KB), lung (A549), brain (U87), liver (HepG2) and normal dermal fibroblast cell line (HDF) using the sulforhodamine B (SRB) assay. Compound 29 comprising two gemcitabine (dFdC) units exhibited the highest activity among dimers 21–30. The activity of compound 29 was higher than that of dFdC in all the studied cancer cell lines. A similar order of activity was observed for compounds 25, 28, and 30. The best activity among all the dimers synthesized was displayed by compound 39, comprising two gemcitabine units with a cleavable linker. The activity of compound 39 was 5 to 9 times higher than that of dFdC, depending on the cell line. In addition, marked cytotoxic activity was shown by compounds 31, 36, 38, and 40.

A Hydrogen Peroxide Activatable Gemcitabine Prodrug for the Selective Treatment of Pancreatic Ductal Adenocarcinoma

The main concern in the use of anticancer chemotherapeutic drugs is host toxicity. Patients need to interrupt or change chemotherapy due to adverse effects. In this study, we aimed to decrease adverse events with gemcitabine (GEM) in the treatment of pancreatic ductal adenocarcinoma and focused on the difference of hydrogen peroxide levels in normal versus cancer cells. We designed and synthesized a novel boronate-ester-caged prodrug that is activated by the high H2O2 concentrations found in cancer cells to release GEM. An H2O2-activatable GEM (A-GEM) has higher selectivity for H2O2 over other reactive oxygen species (ROS) and cytotoxic effects corresponding to the H2O2 concentration in vitro. A xenograft model of immunodeficient mice indicated that the effect of A-GEM was not inferior to that of GEM when administered in vivo. In particular, myelosuppression was significantly decreased following A-GEM treatment compared with that following GEM treatment.

Fluoro-nucleoside and synthesis method thereof

The invention discloses fluoro-nucleoside and a synthesis method thereof. The fluoro-nucleoside comprises the following steps: (1) by taking cytosine and hexamethyl disilazane as raw materials, preparing a cytosine siloxane protection radical solution; (2) dissolving a glycosyl compound into isoamylol, and performing stirring catalysis so as to obtain a glycosyl compound solution; (3) dropping thecytosine siloxane protection radical solution into the glycosyl compound solution, uniformly mixing, keeping the temperature, performing suction filtration, adding hydrochloric acid, stirring to separate a solid, and drying the solid so as to obtain an intermediate; (4) under an acid condition, performing hydroxyl deprotection on the intermediate, thereby obtaining the fluoro-nucleoside. By optimizing reaction conditions, adjusting raw material proportions and adding hydroxyapatite powder, generation and correct selection of target intermediate conformation are ensured, the reaction temperature is reduced, the purity of the fluoro-nucleoside is increased, the purity of the fluoro-nucleoside is as high as 99.8%, meanwhile the operation security is improved, the energy consumption is reduced, the cost is reduced, and the fluoro-nucleoside is applicable to large-scale production and application, can bring good economic benefits to companies and has good prospects.

4-N-Alkanoyl and 4-N-alkyl gemcitabine analogues with NOTA chelators for 68-gallium labelling

The conjugation of 4-N-(3-aminopropanyl)-2′-deoxy-2′,2′-difluorocytidine with 2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (SCN-Bn-NOTA) ligand in 0.1 M Na2CO3 buffer (pH 11) at ambient temperature provided

Difluoronucleoside antimetabolite anticancer drug for destroying cell replication

The invention provides a difluoronucleoside antimetabolite anticancer drug for destroying cell replication as well as preparation and application of pharmaceutical composition of the antimetabolite anticancer drug. The chemical structural formula of the difluoronucleoside antimetabolite anticancer drug for destroying cell replication is shown as (A) in the description. The drug is an important anticancer drug, has the characteristic of wide antitumor spectrum, shows better anticancer activity in various tumors such as non-small cell lung cancer, breast cancer, pancreatic cancer and the like, and is one of the first choices for treatment of the non-small cell lung cancer and also one of the first choices for chemotherapy of pancreatic cancer.

Involvement of CYP4F2 in the metabolism of a novel monophosphate ester prodrug of gemcitabine and its interaction potential in vitro

Compound-3 is an oral monophosphate prodrug of gemcitabine. Previous data showed that Compound-3 was more potent than gemcitabine and it was orally active in a tumor xenograft model. In the present study, the metabolism of Compound-3 was investigated in several well-known in vitro matrices. While relatively stable in human and rat plasma, Compound-3 demonstrated noticeable metabolism in liver and intestinal microsomes in the presence of NADPH and human hepatocytes. Compound-3 could also be hydrolyzed by alkaline phosphatase, leading to gemcitabine formation. Metabolite identification using accurate mass- and information-based scan techniques revealed that Compound-3 was subjected to sequential metabolism, forming alcohol, aldehyde and carboxylic acid metabolites, respectively. Results from reaction phenotyping studies indicated that cytochrome P450 4F2 (CYP4F2) was a key CYP isozyme involved in Compound-3 metabolism. Interaction assays suggested that CYP4F2 activity could be inhibited by Compound-3 or an antiparasitic prodrug pafuramidine. Because CYP4F2 is a key CYP isozyme involved in the metabolism of eicosanoids and therapeutic drugs, clinical relevance of drug-drug interactions mediated via CYP4F2 inhibition warrants further investigation.

Selective Activation of a Prodrug by Thioredoxin Reductase Providing a Strategy to Target Cancer Cells

Elevated reactive oxygen species and antioxidant defense systems have been recognized as one of the hallmarks of cancer cells. As a major regulator of the cellular redox homeostasis, the selenoprotein thioredoxin reductase (TrxR) is increasingly considered as a promising target for anticancer drug development. The current approach to inhibit TrxR predominantly relies on the modification of the selenocysteine residue in the C-terminal active site of the enzyme, in which it is hard to avoid the off-target effects. By conjugating the anticancer drug gemcitabine with a 1,2-dithiolane scaffold, an unprecedented prodrug strategy is disclosed that achieves a specific release of gemcitabine by TrxR in cells. As overexpression of TrxR is frequently found in different types of tumors, the TrxR-dependent prodrugs are promising for further development as cancer chemotherapeutic agents.

Industrial preparation process for key intermediate sulfonated saccharide of Gemcitabine

The invention relates to a preparation method for a compound represented by a formula (I) shown in the description, i.e., a key intermediate sulfonated saccharide of Gemcitabine. The final product is prepared through subjecting a compound represented by a formula (II) shown in the description to sodium borohydride reduction, hydroxyl protection and resolution. The method is simple in process, high in yield and high in product purity and has no need of harsh reaction conditions, thereby being very suitable for industrial production.

Synthesis process of fluoronucleoside

The invention relates to a synthesis process of fluoronucleoside. The synthesis process comprises the following steps: step 1, reflowing cytosine and hexamethyldisilazane under the catalysis effect of ammonium sulfate; adding isopropyl alcohol; raising the temperature to obtain a cytosine silyl ether protective group solution; step 2, dissolving a glycosyl compound into isoamyl alcohol and stirring; adding a catalyst and heating to obtain a glycosyl compound solution; step 3, dropwise adding the glycosyl compound solution into the cytosine silyl ether protective group solution; after dropwise adding, continually keeping heat and reacting for hours; carrying out pumping filtration and dropwise adding hydrochloric acid into filtrate; separating out a solid and drying to obtain an intermediate; and step 4, carrying out hydroxyl de-protection on the intermediate under an acidic condition to prepare the fluoronucleoside. According to the synthesis process provided by the invention, the generation of target intermediate configuration is guaranteed and the temperature is greatly reduced; the requirements on equipment are reduced and the safety of operation is improved; the energy consumption is also reduced and the cost is easy to reduce; and the synthesis process is applicable to large-scale production and application.