MOD-1-030 MOD-1-034

Re-Synthesis of 4-(4-((2-(6-chloropyrazin-2-yl)hydrazineylidene)methyl)phenyl)morpholine (isomer isolation)

Reaction 1-MOD-1-034

Procedure

2-chloro-6-hydrazinylpyrazine (50 mg) was stirred into ethanol (4 mL). 4-morpholinobenzaldehyde (62  mg) was then added and stirred at ambient temperature for 8 hours.

The reaction mixture changed colour from yellow to orange after 8 hours.

Upon completion (as detemrined by TLC analysis (Pet. Ether/ EtOAc 7:3) the solvent was removed under reduced pressure to give the product MOD-1-034 as a orange solid (0.0995 g, 0.31 mmol, 90.17%).

¹H NMR of the product MOD-1-034 was taken in different solvents to compare which was the best solvent and the see isomer seperation. MeOD was determined as the best solvent. The NMR showed that many isomers of the product were afforded.

Reaction 2-MOD-1-030

Procedure

2-chloro-6-hydrazinylpyrazine (50 mg) was stirred into MeCN (1 mL). 4-morpholinobenzaldehyde (62  mg) and AcOH (0.045 mL) was then added and stirred at ambient temperature for 8 hours.

The reaction mixture changed colour from yellow to red after 8 hours.

Upon completion (as detemrined by TLC analysis (Pet. Ether/ EtOAc 7:3) the solvent was removed under reduced pressure to give the product MOD-1-030 as a red solid (0.1048g, 0.33 mmol, 92.23%).

¹H NMR of the product MOD-1-034 was taken in different solvents to compare which was the best solvent and the see isomer seperation. MeOD was determined as the best solvent. The NMR showed that many isomers of the product were afforded.

Isomer Seperation

Due to both MOD-1-030 and MOD-1-034 containing isomers the products were combied. The best solvent system was determined as (Toluene/Acetone 19:1).

The crude mixture was purified via flash chromatography on silica gel (Toluene/Acetone 19:1). Forming fractions MOD-1-034-3-4, MOD-1-034-5-42, MOD-1-034-43-54. The fractions all contained isomers and therfore were not successfully seperated. 

References

1.T. York, Open Source Malaria, Malaria.ourexperiment.org, 2016.

2.C. Xia, Open Source Malaria, Malaria.ourexperiment.org, 2016.

3.B. Xie, Open Source Malaria, Malaria.ourexperiment.org, 2016.

MOD-1-026

Synthesis of 4-(4-(5-chloro-[1,2,4]triazolo[4,3-a]pyrazin-3-yl)phenyl)morpholine

Procedure

4-(4-((2-(6-chloropyrazin-2-yl)hydrazineylidene)methyl)phenyl)morpholine (313 mg, 0.99 mmol) was stirred into a flask with  CH₂Cl₂ (18 mL) at room temperature. PhI(OAc)₂ (318 mg, 0.99 mmol)  was added and stirred for 2 hrs. A yellow colour was formed.  

TLC analysis showed the reaction was incomplete (Pet. Ether/EtOAc 7:3).

PhI(OAc)₂ (0.031 g) and DCM (4.0 mL) were added to the mixture and the reaction was left stirring for 18 hrs. An orange solution was formed.

TLC analysis (Pet. Ether/EtOAc 1:1) showed the presence of many products.

The organic layer was washed with saturated NaHCO₃ solution (30 mL). The inorganic layer was extracted with DCM (3 x 20 mL). The combined organic layers were dried over MgSO₄, filtered and the solvent removed in vacuo. Yielding crude product MOD-1-026.

The crude product was purified by flash column chromatography on silica (EtOAc/pet.ether 1:1) yielding several frctions MOD-1-026-A (7.1 mg), MOD-1-026-B (55 mg), MOD-1-026-C (37 mg), MOD-1-026-D (3.6 mg), MOD-1-026-E (66 mg) and MOD-1-026-F (62 mg).

Upon analysis of NMR each fraction contained many isomers as shown in the TLC's of the fractions. Efforts for the last few weeks of project will turn to seperation of the isomers through the use of different solvents for the column and reaction for the condensation step ref. MOD-1-022 (See this link for previous experiment Synthesis of 4-(4-((2-(6-chloropyrazin-2-yl)hydrazineylidene)methyl)phenyl)morpholine)

MOD-1-022

Synthesis of 4-(4-((2-(6-chloropyrazin-2-yl)hydrazineylidene)methyl)phenyl)morpholine

Procedure

2-chloro-6-hydrazinylpyrazine (0.2 g) was stirred into ethanol (10 mL). 4-morpholinobenzaldehyde (0.265 g) was then added and stirred at ambient temperature for 8 hours.

The reaction mixture changed colour from yellow to orange/red after 2 hours.

Upon completion (as detemrined by TLC analysis (Pet. Ether/ EtOAc 1:1) the solvent was removed under reduced pressure to give the product MOD-1-022 as a red solid (0.4043g, 1.27 mmol, 92.16%).

¹H NMR of the product MOD-1-022 was taken in DMSO as the product did not dissolve well in CDCl₃. The NMR showed that many isomers of the product were afforded.

References

1.T. York, Open Source Malaria, Malaria.ourexperiment.org, 2016.

2.C. Xia, Open Source Malaria, Malaria.ourexperiment.org, 2016.

3.B. Xie, Open Source Malaria, Malaria.ourexperiment.org, 2016.

MOD-1-016

Nucleophilic aromatic substitution- Synthesis of 4-morpholinobenzaldehyde (N15) (Scale up)

Procedure

P-fluorobenzaldehyde (1.00 g, 0.87 mL, 8.0 mmol) was added to DMF (15 mL). Morpholine (0.905 mg, 0.89 ml, 10.4 mmol) and then potassium carbonate (2.23 g, 20.16 mmol) were then added sequentially and the reaction stirred at ambient temperature for 0.5 hours.

The reaction mixture was then heated for 24 hours to 100^oC. 

Upon completion (as determined by TLC analysis (Pet. Ether/ EtOAc 5:3)). The reaction mixture was cooled to room temperature, and diluted with water and then extracted into EtOAc. The organic layer was then dried with MgSO₄ and the solvent was removed under reduced pressure.

The crude product was purified by flash chromatography on silica gel (Pet. Ether/Diethyl Ether 4:1) to give the product MOD-1-016 as a colourless solid (1.2924 g, 0.81mmol, 84%)

TLC analysis of the fractions showed good separation of the products.

¹H NMR (MOD-1-016-A) fractions 5-6, (MOD-1-016-B) fractions 8-11 and (MOD-1-016-C) fractions 14-35 showed that MOD-1-016-C was the product. 

Analysis of MOD-1-016-C (Product)

Yield 84% yellow solid m.p: 65-69^oC. R.f=0.24 (Pet. Ether/ EtOAc 5:3).  ¹H NMR (400 MHz CDCl₃) δ 9.80 (1H, s, CHO), 7.77 (2H, d, J=9.2 Hz CHAr) 6.92 (2H, d, J 8.9 Hz, CH_Ar), 3.87−3.85(4H, m, CH₂), 3.37−3.34 (4H, m, CH₂)

References

1. C. Tintori, A. Brai, M. Dasso Lang, D. Deodato, A. Greco, B. Bizzarri, L. Cascone, A. Casian, C. Zamperini, E. Dreassi, E. Crespan, G. Maga, G. Vanham, E. Ceresola, F. Canducci, K. Ariën and M. Botta, J. Med. Chem., 2016, 59, 2747-2759.

2. M. Abdel-Atty, N. Farag, S. Kassab, R. Serya and K. Abouzid, Bioorg. Chem., 2014, 57, 65-82.

 MOD-1-011

Nucleophilic aromatic substitution- Synthesis of 4-morpholinobenzaldehyde (N15)

Procedure

P-fluorobenzaldehyde (200 mg, 0.173 mL, 1.6 mmol) was added to DMF (3 mL). Morpholine (0.150mg g, 0.152 ml, 1.6 mmol) and then potassium carbonate (445 mg, 4.12 mmol) were then added sequentially and the reaction sired at ambient temperature for 0.5 hours.

The reaction mixture was then heated for 24 hours to 100^oC. 

Upon completion (as detemrined by TLC analysis (Pet. Ether/ EtOAc 5:3)). The reaction mixture was cooled to room temperature, and diluted with water and then extracted into dichloromethane. The organic layer was then dried with MgSO₄ and the solvent was removed under reduced pressure.

The crude product was purified by flash chromatography on silica gel (Pet. Ether/Diethyl Ether 4:1) to give the product MOD-1-011 as a colourless solid (0.1562g, 0.81mmol, 51%)

TLC analysis of the fractions showed good separation of the products.

¹H NMR (MOD-1-011-A) fractions 3-4, (MOD-1-011-B) fractions 5-9 and (MOD-1-011-C) fractions 15-25 showed that MOD-1-011-C was the product. 

Analysis of MOD-1-011-C (Product)

Yield 51% white solid m.p: 65-69^oC. R.f=0.24 (Pet. Ether/ EtOAc 5:3).  ¹H NMR (400 MHz CDCl₃) δ 9.80 (1H, s, CHO), 7.77 (2H, d, J=9.2 Hz CHAr) 6.92 (2H, d, J 8.8 Hz, CH_Ar), 3.87−3.85(4H, m, CH₂), 3.37−3.34 (4H, m, CH₂). ¹³C  NMR (100 Mhz CDCl₃) δ 190.50 (CHO), 155.14 (C_Ar), 131.81(CH_Ar), 127.66(C_Ar), 113.45 (CH_Ar), 66.50 (C_Quat), 47.29 (C_Quat) ν_max (ATR) /cm^-1 2964, 2851, 1667, 1596, 1222, 1170, 820, cm^-1. HRMS (ESI+) C₁₁H₁₄NO₂ [M+H]⁺ Requires:

found 192.1019.

References

1. C. Tintori, A. Brai, M. Dasso Lang, D. Deodato, A. Greco, B. Bizzarri, L. Cascone, A. Casian, C. Zamperini, E. Dreassi, E. Crespan, G. Maga, G. Vanham, E. Ceresola, F. Canducci, K. Ariën and M. Botta, J. Med. Chem., 2016, 59, 2747-2759.

2. M. Abdel-Atty, N. Farag, S. Kassab, R. Serya and K. Abouzid, Bioorganic Chemistry, 2014, 57, 65-82.