Heterocyclic Building Blocks-piperazine

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.109-07-9,2-Methylpiperazine,as a common compound, the synthetic route is as follows.

Into a reactor with a working volume of 1000 mL equipped with a thermometer, a reflux condenser and a mechanical stirrer, DMSO (480 mL), l-cyclopropyl-6,7-difluoro-l,4-dihydro-8-methoxy-4-oxo-3-quinoline carboxylic acid (138.0 g; 0.4675 mole) and 2-methylpiperazine (94.0 g; 0.9387 mole) were put at 25C (20C-30C). The reaction mixture was stirred for 30 minutes at 25C (20C-30C). Then it was heated in 50 minutes (45-60 minutes) to the temperature of 73C. The reaction mixture was stirred at this temperature for 12 hours. After 12 hours at 73C, the reaction mixture was cooled to 25C in 45 minutes (40-50 minutes). The pH of the suspension was measured and adjusted to the pH value of 10.2 with a 15% HC1 solution (27.5 mL of 15% HC1) and the suspension was stirred for 24 hours. The pHof the suspension was periodically checked and adjusted to the desired value of 10.2 if necessary. When adjusting the pH vapours were formed, which were sucked off by underpressure and led through a trap with a solution of calcium hydroxide, which irreversibly bound fluoride ions. The product was then filtered over a filter MN 640 (black ribbon) and washed with methanol (165 mL). The product was thoroughly sucked off and the humidity was determined. Estimated yield of the dry gatifloxacin base: 52.0-54.7%., 109-07-9

As the paragraph descriping shows that 109-07-9 is playing an increasingly important role.

Reference：
Patent; KRKA, TOVARNA ZDRAVIL, D.D., NOVO MESTO; WO2006/4561; (2006); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

78818-15-2, Benzyl 3-oxopiperazine-1-carboxylate is a piperazines compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated,78818-15-2

b) 2-Bromoethyl di-tert-butyl phosphate (298mg, 0. 94MMOL) in tetrahydrofuran (1. 0ml) was added at room temperature to a stirred suspension of benzyl 3-oxopiperazine-1- carboxylate (200mg, 0. 85mmol), powdered potassium hydroxide (57mg, L. OMMOL) and tetra- n-butylammonium bromide (55mg, 0.17mmol) in THF (2. 0ml). The reaction mixture was -266- stirred for 90 minutes and then filtered through Celite and the filtrate evaporated to leave a colourless oil. The crude product was purified by silica gel chromatography eluting with a 2- 5% mixture of methanol in dichloromethane to give benzyl 4-{2-[(DI-TERT- butoxyphosphoryl) oxy] ETHYL}-3-OXOPIPERAZINE-1-CARBOXYLATE (220 mg, 55% yield) as a colourless oil: 1H-NMR (CDC13) : 7.34 (m, 5H), 5.16 (s, 2H), 4.15 (s, 2H), 4.11 (m, 2H), 3.71 (m, 2H), 3.65 (m, 2H), 3.53 (m, 2H), 1.47 (s, 18H).

The synthetic route of 78818-15-2 has been constantly updated, and we look forward to future research findings.

Reference：
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2004/94410; (2004); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.120737-78-2,tert-Butyl 2-methylpiperazine-1-carboxylate,as a common compound, the synthetic route is as follows.

[00203] Under a N2 atmosphere tert-butyl 2-methylpiperazine-l-carboxylate (2.0 mmol), (E)-(3-bromoprop-l-en-l-yl)benzene (2.4mmol), K2CO3 (3 mmol) were combined in a vial, CH3CN (2 mL) was added, and the reaction mixture was stirred at 60 C overnight, The crude reaction mixture was diluted with EtOAc and washed with H20 and brine. The organic layer was dried over Na2S04, filtered and condensed. The crude mixture was purified using flash silica gel column chromatography to get the pure product tert-butyl 4-cinnamyl-2- methylpiperazine-l-carboxylate (yield 70%).

120737-78-2, As the paragraph descriping shows that 120737-78-2 is playing an increasingly important role.

Reference：
Patent; THE GENERAL HOSPITAL CORPORATION; PETERSON, Randall T.; RENNEKAMP, Andrew J.; KOKEL, David; (121 pag.)WO2015/200674; (2015); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

21043-40-3, 1-Cyclopentylpiperazine is a piperazines compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

General procedure: One-pot synthesis of N-(aminosulfonyl)-4-podophyllotoxin carbamates from PPT in the presence of CSI and amine via the Burgess-type intermediates.1 CSI (170 mg, 1.2 mmol) was added dropwise to a solution of PPT (500 mg, 1.2 mmol) in DCM (5 mL) at -10. The reaction mixture was stirred at -10 for 30 min. Pyridine (1.0 equiv) was then added dropwise to above mixture and stirred for another 1 h at -10. Followed amine (2.0 equiv) was added to the reaction mixture at -10. The reaction mixture was stirred for 2 h at -10, then stirred at room temperature until the reaction was finished. The reaction mixture was washed in order by distilled water and saturated brine, and then the extract was dried over MgSO4 and concentrated in vacuo. The residue was purified by silica gel column chromatography, using CH2Cl2/acetone as the eluent, to afford pure compounds 5-13.

21043-40-3, As the paragraph descriping shows that 21043-40-3 is playing an increasingly important role.

Reference：
Article; Xu, Xiao-Hui; Guan, Xiao-Wen; Feng, Shi-Liang; Ma, You-Zhen; Chen, Shi-Wu; Hui, Ling; Bioorganic and Medicinal Chemistry Letters; vol. 27; 13; (2017); p. 2890 – 2894;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.76003-29-7,1-Boc-3-Oxopiperazine,as a common compound, the synthetic route is as follows.,76003-29-7

-(tert-Butyloxycarbonyl)-piperazin-2-one (8.0 g, 40 mmol), EXAMPLE 40, is dissolved in THF (160 mL), cooled in an ice bath and treated with 60% sodium hydride (1.9 g, 48 mmol). The reaction mixture is stirred 40 minutes, then treated with tetra-butylammon

76003-29-7 1-Boc-3-Oxopiperazine 3157178, apiperazines compound, is more and more widely used in various fields.

Reference：
Patent; AVENTIS PHARMACEUTICALS INC.; US2004/102450; (2004); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

5747-48-8,With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.5747-48-8,11-(Piperazin-1-yl)dibenzo[b,f][1,4]thiazepine,as a common compound, the synthetic route is as follows.

A 1 liter round bottom flask equipped with stirring rod, thermo pocket, water condenser was charged with solution of l l-piperazinyldibenzo[b,f] [l,4]thiazepine in toluene 350 cc [63.0 g (0.22 moles)] and the mixture was stirred for 15 min 25- 30C, and was added sodium carbonate [41.0 gm (0.39 moles)], tetra butyl ammonium bromide [16.0 gm (0.05 mole)] and 2-(2-chloroethoxy)ethanol [32.0 gm (0.257 moles)] at room temperature. The reaction mixture was heated to reflux at 110- 112C. The reaction mixture was maintained at reflux for 10-12 hrs. The reaction mixture was analyzed by HPLC (to check for absence of compound of Formula IV) and was cooled to 25C to 30C. To which, was added 150 cc DM water, then the reaction mixture was stirred for 30 min at 25-30C. The layers were separated and the aqueous layer extracted with 50 cc toluene. The extract and the organic layer were combined, to which was added 250 cc water and was acidified with acetic acid to obtain a pH of 2-3. The reaction mixture was stirred for 30 min at 25-30C. The layers were separated and the aqueous layer washed with 100 cc toluene twice. To the aqueous layer was added 250 cc toluene, and the pH was adjusted to 8-10 using sodium carbonate, the reaction mixture was stirred for 30 min at 25-30C. The layers were separated and the aqueous layer extracted with 125 cc toluene. The extract and the organic layer were combined, to which was washed with DM (dimineralized) water 300 cc twice. The organic layer was distilled off under vacuum below 70C to afford 2-(2-(4-dibenzo[b,f]-[l,4] thiazepine-l l-yl-l-piperazinyl)ethoxy) ethanol. Purity of 2-(2-(4-dibenzo[b,fj-[l,4] thiazepine-l l-yl-l-piperazinyl)ethoxy) ethanol was 99.0% (area % by HPLC).

The synthetic route of 5747-48-8 has been constantly updated, and we look forward to future research findings.

Reference：
Patent; TEVA PHARMACEUTICAL INDUSTRIES LTD.; TEVA PHARMACEUTICALS USA, INC.; WO2008/121415; (2008); A2;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.54699-92-2,4-Methyl-1-piperazineacetic acid,as a common compound, the synthetic route is as follows.

54699-92-2, 36) 2-(4-methylpiperazin-1-yl)acetyl chloride [Show Image] Oxalil chloride (0.3 ml, 3.47 mmol) was added dropwise to a stirred solution of (4-Methyl-piperazin-1-yl)-acetic acid (500 mg, 3.16 mmol) 15 ml of dry THF and placed under inert atmosphere. Two drops of dimethylformammide were added. The reaction mixture was refluxed for 1 h, and the solvent removed under reduced pressure giving 440 mg (80%) (4-Methyl-piperazin-1-yl)-acetyl chloride as a yellow solid. 1H-NMR (DMSO, 400 MHz), delta (ppm): 3.20 (2H, s), 2.78 (8H, m), 2.60 (3H, s).

54699-92-2 4-Methyl-1-piperazineacetic acid 2762732, apiperazines compound, is more and more widely used in various fields.

Reference：
Patent; Universita Degli Studi Di Milano – Bicocca; UNIVERSITE DE GENEVE; UNIVERSITE CLAUDE BERNARD – LYON 1; EP2107054; (2009); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

138775-02-7, (R)-4-((Benzyloxy)carbonyl)-1-(tert-butoxycarbonyl)piperazine-2-carboxylic acid is a piperazines compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

PREPARATIVE EXAMPLE 5; The title compound from Prepartive Example 4 (9.6 gm, 26.3 mmol) was dissolved in absoluteEtOH (100 mL) in a hydrogenation vessel. The vessel was flushed with N2 and 10% Pd/C (3.0g, 50% by weight with water) was added. The mixture was hydrogenated at 55 psi of H2 for 18 hours during which time a precipitate formed. When the reaction was complete (TLC, 30% MeOH/NH3/CH2Cl2), the reaction mixture was filtered through a pad of celite, and the pad washed with EtOH followed by distilled H2O. The filtrate was evaporated to ?1/3 the volume and distilled H2O (200 mL) was added. The resulting solution was extracted with EtOAc (contains pure N,N-Di-Boc-2-carboxy-piperazine which was saved). The water layer was evaporated to dryness with azeotropic removal of residual H2O with methanol (2X) to give pure product (3.98g)., 138775-02-7

The synthetic route of 138775-02-7 has been constantly updated, and we look forward to future research findings.

Reference：
Patent; SCHERING CORPORATION; EP1140904; (2005); B1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

21043-40-3, 1-Cyclopentylpiperazine is a piperazines compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

A mixture of 5.6 g (35 mmol) 2-chloro-4-nitropyridine, 5.75 g (37 mmol) 1-cyclo- pentyl piperazine and 4,59 g (35 mmol) N,N-diisopropylethylamine in 35 ml DMF and 12 ml water was heated to 95 0C for 3 h . After evaporation to dryness the residue was taken up in 150 ml NaHCO3 aq. and 150 ml ethyl acetate. The aqueous phase was extracted two times with 150 ml ethyl acetate each and the combined organic phases were washed twice with 10O1 ml NaHCO3 aq each and 100 ml NaCl aq. sat. and dried with MgSO4 and evaporated to dryness. The residue was purified with columnchromatography to^yield 2.85 g (29 %) l-cyclopentyl-4~(4-nitro-pyridin-2-yl)- piperazine (m/e): 277.3 (MH+; 100%) and 4.47 g (47 %) l-(2-chloro-pyridin-4-yl)-4- cyclopentyl-piperazine (m/e): 266.3 (MH+; 100%)., 21043-40-3

As the paragraph descriping shows that 21043-40-3 is playing an increasingly important role.

Reference：
Patent; F.HOFFMANN-LA ROCHE AG; WO2006/63718; (2006); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics

109-07-9, 2-Methylpiperazine is a piperazines compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

A mixture of 2,3-dichloropyrazine (2.80 g, 18.8 mmol), racemic 2- methylpiperazine (1.88 g, 18.8 mmol) and K2CO3 (3.90 g, 28.2 mmol) in acetonitrile (25 mL) was heated at 65 C for 15 h with stirring. The reaction mixture was filtered and concentrated. The crude product was purified by flash chromatography on silica gel using CHCl3/MeOH (15: 1) as eluent to give 3.2 g (79%) of the title compound. MS m/z 213 (M+H) +., 109-07-9

As the paragraph descriping shows that 109-07-9 is playing an increasingly important role.

Reference：
Patent; BIOVITRUM AB; WO2004/9586; (2004); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics