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2. Debate teórico-conceptual

2.1. La configuración de la actividad informal

Synthesis of Compound 3.1a.Poly(ethylene glycol) monomethylether (PEGMME) (2000

g/mol) (5.00 g, 2.5 mmol, 1.0 equiv) and succinic anhydride (2.50 g, 25 mmol, 10 equiv) were dissolved in 50 mL of dry CH2Cl2 and stirred at room temperature for 5 min. NEt3

(7.0 mL, 50 mml, 20 equiv) and DMAP (0.32 g, 2.5 mmol, 1 equiv) were added and the solution was refluxed at 45˚C for 24 h. The reaction mixture was diluted with CH2Cl2 and

poured over 1:1 1M HCl:brine. The product was re-extracted from the aqueous layer 5 times using CH2Cl2. The combined organic layers were dried over MgSO4, filtered, and

concentrated in vacuo. The crude product was then dissolved in 10 mL of DMF and dialyzed against DMF for 24 h (1 L, 1 solvent change) using a regenerated cellulose membrane (3500 g/mol MWCO). The contents of the dialysis membrane were then concentrated in vacuo and lyophilized to afford compound 3.1a (4.12 g, 78%). 1H NMR (CDCl3, 600 MHz): δ 4.28-4.23 (m, 2H), 3.89-3.43 (m, 170H), 3.37 (s, 3H), 2.68-2.58

(m, 6H).

Synthesis of Compound 3.1b.Compound 3.1b was synthesized using an identical

procedure to 3.1a except that 5000 g/mol molecular weight PEGMME was used in place of 2000 g/mol molecular weight PEGMME. The quantities of reagents used were

PEGMME (5000 g/mol) (4.99 g, 1.0 mmol, 1.0 equiv), succinic anhydride (1.00 g, 10 mmol, 10 equiv), NEt3 (2.0 mL, 20 mmol, 20 equiv), and DMAP (0.13 g, 1 mmol, equiv).

The crude product was purified through dialysis against DMF using a regenerated

cellulose membrane (3500 g/mol MWCO) and lyophilized to afford compound 3.1a (4.34 g, 85%). 1H NMR (CDCl

3, 600 MHz): δ 4.25-4.22 (m, 2H), 3.81-3.44 (m, 574H), 3.36 (s,

3H), 2.66-2.58 (m, 6H).

Synthesis of Compound 3.2a. Compound 3.1a (2.96 g, 1.41 mmol, 1.0 equiv) was

dissolved in 30 mL of dry CH2Cl2. Pyridine (3.10 mL, 28.2 mmol, 20 equiv) and 4-

nitrophenyl chloroformate (2.85 g, 14.2 mmol, 10 equiv) were successively added and the solution was stirred at room temperature for 24 h. The reaction mixture was diluted with CH2Cl2 and poured over 1:1 1M HCl:brine. The product was re-extracted from the

aqueous layer 5 times using CH2Cl2. The combined organic layers were dried over

MgSO4, filtered, and concentrated in vacuo to a volume of approximately 5 mL. The

crude product was then precipitated out of 300 mL of cold Et2O to afford 3.2a (2.80 g,

89%). 1H NMR (CDCl3, 600 MHz): δ 8.24 (m, 2H), 7.28 (m, 2H), 4.29-4.23 (m, 2H),

3.83-3.40 (m, 180H), 3.65 (s, 3H), 2.92-2.85 (m, 2H), 2.81-2.74 (m, 2H). MS (MALDI- TOF) [M+Na]+: 1904.9.

Synthesis of Compound 3.2b. Compound 3.2b was synthesized using an identical

procedure to 3.2a. The quantities of reagents used were 3.1b (4.08 g, 0.80 mmol, 1 equiv), 4-nitrophenyl chloroformate (1.61 g, 8.0 mmol, 10 equiv), and pyridine (1.74 mL, 16.0 mmol, 20 equiv). The crude product was precipitated out of 500 mL of cold Et2O to

afford 3.2b (3.85 g, 92%). 1H NMR (CDCl3, 600 MHz): δ 8.25 (m, 2H), 7.29 (m, 2H),

4.28-4.26 (m, 2H), 3.77-3.48 (m, 591H), 3.36 (s, 3H), 2.92-2.88 (m, 2H), 2.81-2.76 (m, 2H).

Synthesis of Compound 3.4a. Compound 3.2a (2.72 g, 1.22 mmol, 1.0 equiv) was

dissolved in 30 mL of dry CH2Cl2. NEt3 (3.40 mL, 24.4 mmol, 20 equiv) and 3.3 (2.95 g,

12.4 mmol, 10 equiv) were successively added and the solution was stirred at room temperature for 24 h. The reaction mixture was diluted with CH2Cl2 and poured over 1:1

Cl2. The combined organic layers were dried over MgSO4, filtered, and concentrated in

vacuo to a volume of approximately 5 mL. The crude product was then precipitated out

of 300 mL of cold Et2O to afford 3.4a (2.17 g, 77%). 1H NMR (CDCl3, 600 MHz): δ 7.28

(m, 2H), 7.01 (m, 2H), 4.69 (s, 2H), 4.27-4.21 (m, 2H), 3.86-3.41 (m, 190H), 3.35 (s, 3H), 2.88-2.82 (m, 2H), 2.78-2.70 (m, 2H). MS (MALDI-TOF) [M+Na]+: 2092.2.

Synthesis of Compound 3.4b. Compound 3.4b was synthesized using an identical

procedure to 3.4a. The quantities of reagents used were 3.2b (4.08 g, 0.80 mmol, 1 equiv), 3.3 (1.88 g, 7.8 mmol, 10 equiv) and NEt3 (2.20 mL, 15.7 mmol, 20 equiv). The

crude product was precipitated out of 400 mL of cold Et2O to afford 3.4b (3.47 g, 86%). 1H NMR (CDCl

3, 600 MHz): δ 7.30 (m, 2H), 7.03 (m, 2H), 4.70 (s, 2H), 4.28-4.24 (m,

2H), 3.82-3.47 (m, 590H), 3.37 (s, 3H), 2.89-2.84 (m, 2H), 2.78-2.74 (m, 2H).

Synthesis of Compound 3.5a. Compound 3.4a (2.12 g, 0.91 mmol, 1.0 equiv) was

dissolved in 25 mL of 1% HCl in 3:1 EtOH:CH2Cl2 and stirred at room temperature for 1

h. The reaction mixture was diluted with CH2Cl2 and poured over saturated NaHCO3. The

product was re-extracted from the aqueous layer 5 times using CH2Cl2. The combined

organic layers were dried over MgSO4, filtered, and concentrated in vacuo to a volume of

approximately 5 mL. The crude product was then precipitated out of 300 mL of cold Et2O

to afford 3.5a (1.50 g, 75%). 1H NMR (CDCl3, 600 MHz): δ 7.36 (m, 2H), 7.06 (m, 2H),

4.65 (s, 2H), 4.29-4.23 (m, 2H), 3.83-3.40 (m, 181H), 3.36 (s, 3H), 2.90-2.83 (m, 2H), 2.79-2.73 (m, 2H). MS (MALDI-TOF) [M+Na]+: 2066.1.

Synthesis of Compound 3.5b. Compound 3.5b was synthesized using an identical

procedure to 3.5a. The quantities of reagents used were 3.4b (3.54 g, 0.67 mmol, 1 equiv). The crude product was precipitated out of 400 mL of cold Et2O to afford 3.5b

(2.84 g, 81%). 1H NMR (CDCl3, 600 MHz): δ 7.29 (m, 2H), 7.02 (m, 2H), 4.70 (s, 2H),

4.28-4.23 (m, 2H), 3.81-3.45 (m, 558H), 3.36 (s, 3H), 2.89-2.83 (m, 2H), 2.79-2.72 (m, 2H).

Synthesis of Compound 3.6a. Compound 3.5a (0.50 g, 0.23 mmol, 1.0 equiv) was

dissolved in 8 mL of dry CH2Cl2. Pyridine (0.40 mL, 4.6 mmol, 20 equiv) and 4-

reaction mixture was stirred at room temperature for 24 h. The reaction mixture was diluted with CH2Cl2 and poured over 1:1 1M HCl:brine. The product was re-extracted

from the aqueous layer 5 times using CH2Cl2. The combined organic layers were dried

over MgSO4, filtered, and concentrated in vacuo to a volume of approximately 3 mL. The

crude product was then precipitated out of 80 mL of cold Et2O to afford 3.6a (0.44 g,

86%). 1H NMR (CDCl

3, 600 MHz): δ 8.26 (m, 2H), 7.45 (m, 2H), 7.37 (m, 2H), 7.14 (m,

2H), 5.27 (s, 2H), 4.29-4.24 (m, 2H), 3.84-3.41 (m, 191H), 3.37 (s, 3H), 2.92-2.84 (m, 2H), 2.80-2.73 (m, 2H). MS (MALDI-TOF) [M+Na]+: 2231.2.

Synthesis of Compound 3.6b. Compound 3.6b was synthesized using an identical

procedure to 3.6a. The quantities of reagents used were 3.5b (0.99 g, 0.19 mmol, 1 equiv), pyridine (0.31 mL, 3.8 mmol, 20 equiv), and 4-nitrophenyl chloroformate (0.38 g, 1.9 mmol, 10 equiv). The crude product was precipitated out of 100 mL of cold Et2O to

afford 3.6b (0.85 g, 83%).1H NMR (CDCl3, 600 MHz): δ 8.25 (m, 2H), 7.44 (m, 2H),

7.36 (m, 2H), 7.13 (m, 2H), 5.26 (s, 2H), 4.28-4.23 (m, 2H), 3.84-3.41 (m, 566H), 3.35 (s, 3H), 2.90-2.84 (m, 2H), 2.79-2.73 (m, 2H).

Synthesis of Polymer 3.7a. Activated monomer 2.1c19 (1.02 g, 2.0 mmol, 1.0 equiv) was

dissolved in 3 mL of 1:1 TFA:CH2Cl2 and stirred at room temperature for 2 h. The

solvent was then removed under a stream of nitrogen in the fume hood prior to subjecting the reaction mixture three times to a repeat cycle of dilution with CH2Cl2 followed by

concentration under reduced pressure to remove residual TFA and provide the

deprotected monomer 2.5.19 End-cap 3.6a (0.22 g, 0.10 mmol, 0.05 equiv) was added and the resulting mixture was dissolved in 8 mL of anhydrous toluene and stirred at room temperature for 5 min. NEt3 (1.4 mL, 10 mmol, 5.0 equiv) and DMAP (62 mg, 0.50

mmol, 0.25 equiv) were sequentially added and the solution was then cooled to -15˚C and stirred for 24 h. The solution was then warmed to room temperature and stirred for an additional 36 h. The reaction mixture was diluted with CH2Cl2 and poured over 1:1 1 M

citric acid:brine and extracted from the aqueous layer 5 times with CH2Cl2. The

combined organic layers were then washed with saturated NaHCO3 and extracted from

the aqueous layer an additional 5 times with CH2Cl2. The combined organic layers were

in 2 mL of DMF and dialyzed against DMF for 24 h (200 mL, 1 solvent change) using a regenerated cellulose membrane (25000 g/mol MWCO). The contents of the dialysis membrane were then concentrated in vacuo and lyophilized to afford polymer 3.7a (0.29 g, 40%). 1H NMR indicated a degree of polymerization of 18 by integrating the

benzylic peak against the PEG end-cap. 1H NMR (CDCl3, 600 MHz): δ 7.44-7.28 (br,

36H), 7.14-7.00 (br, 35H), 5.16-5.04 (m, 35 H), 4.29-4.25 (m, 2H), 3.81-3.40 (m, 369H), 3.38 (s, 4H), 3.21-2.84 (m, 102H), 2.80-2.74 (m, 2H).SEC: Mn=3600g/mol, Mw=5290

g/mol, PDI=1.47 (PEG standards).

Synthesis of Polymer 3.7b. Activated monomer 2.1c19 (1.02 g, 2.0 mmol, 1.0 equiv) was

dissolved in 3 mL of 1:1 TFA:CH2Cl2 and stirred at room temperature for 2 h. The

solvent was then removed under a stream of nitrogen in the fume hood prior to subjecting the reaction mixture three times to a repeat cycle of dilution with CH2Cl2 followed by

concentration under reduced pressure to remove residual TFA and provide the

deprotected monomer 2.5.19 End-cap 3.6b (0.51 g, 0.10 mmol, 0.05 equiv) was added and the resulting mixture was dissolved in 8 mL of anhydrous toluene and stirred at room temperature for 5 min. NEt3 (1.4 mL, 10 mmol, 5.0 equiv) and DMAP (62 mg, 0.50

mmol, 0.25 equiv) were sequentially added and the solution was stirred at -15˚C for 24 h. The reaction was then warmed to room temperature and stirred for an additional 36 h. The reaction mixture was diluted with CH2Cl2 and poured over 1:1 1M citric acid:brine

and extracted from the aqueous layer 5 times with CH2Cl2. The combined organic layers

were then washed with saturated NaHCO3 and extracted from the aqueous layer an

additional 5 times with CH2Cl2. The combined organic layers were dried over MgSO4,

filtered, and concentrated in vacuo. The crude polymer was dissolved in 2 mL of DMF and dialyzed against DMF for 24 h (200 mL, 1 solvent change) using a regenerated cellulose membrane (25000 g/mol MWCO). The contents of the dialysis membrane were then concentrated in vacuo and lyophilized to afford polymer 3.7b (0.55 g, 51%). 1H

NMR indicated a degree of polymerization of ∼ 10 by integrating the benzylic peak against the PEG end-cap. 1H NMR (CDCl

3, 600 MHz): δ 7.41-7.27 (br, 20H), 7.12-7.00

3.16-2.83 (m, 56H), 2.79-2.74 (m, 2H). SEC: Mn=7170g/mol, Mw=8650g/mol,

PDI=1.21 (PEG standards).

Synthesis of Compound 3.11.Compound 3.835 (0.88 g, 2.9 mmol, 1.4 equiv) was

dissolved in 3 mL of 1:1 TFA:CH2Cl2 and stirred at room temperature for 2 h. The

solvent was then removed under a stream of nitrogen in the fume hood prior to subjecting the reaction mixture three times to a repeat cycle of dilution with CH2Cl2 followed by

concentration under reduced pressure to remove residual TFA and provide the Boc- deprotected compound 3.9. Compound 3.10 (2.0 mmol, 1.0 equiv) was added and the resulting mixture was dissolved in 10 mL of anhydrous toluene. DIPEA (1.80 mL, 10.3 mmol, 5.3 equiv) and DMAP (40 mg, 0.4 mmol, 0.2 equiv) were successively added to the reaction flask and the solution was stirred at room temperature overnight. The reaction mixture was diluted with CH2Cl2 and washed once with 1 M HCl, twice with 1

M Na2CO3, and once with brine. The organic layer was then dried over MgSO4, filtered,

and concentrated in vacuo. The resulting oil was purified through silica gel

chromatography (1:9 EtOAc:CH2Cl2) to afford compound 3.11 as a pale yellow oil (0.65

g, 71%). 1H NMR (CDCl3, 600 MHz): δ 8.49 (d, J=4.8, 1H), 7.74-7.59 (m, 2H), 7.29 (m,

2H), 7.12-7.09 (m, 1H), 7.08-7.00 (m, 2H), 4.71 (s, 2H), 3.76 & 3.66 (m, rotamers, 2H), 3.14 & 3.03 (m, rotamers, 3H), 3.10-3.03 (m, 2H), 0.93 (s, 9H), 0.09 (s, 6H). 13C NMR (CDCl3, 100 MHz): δ 159.8, (154.9 &154.7, rotamers), (150.2 & 149.9, rotamers), 138.5,

137.2, 127.0, 121.5, 121.4, (121.0 & 120.9, rotamers), (120.1 & 120.0, rotamers), 64.6, (49.0 & 48.4, rotamers),(36.6, 36.1, & 35.9, rotamers), 26.0, 18.5, -5.1. FT-IR

(νmax/cm−1): 2955, 2930, 2885, 2856, 1722, 1574, 1562, 1510. HRMS: calcd [M]+

(C22H32N2O3S2Si): 464.1624. Found (EI): 464.1619.

Synthesis of Compound 3.12. Compound 3.11 (0.49 g, 1.1 mmol, 1 equiv) was dissolved

in 4 mL of 1% HCl in EtOH and stirred at room temperature for 1.5 h. The reaction mixture was diluted with CH2Cl2 and washed with saturated NaHCO3. The organic layer

was then dried over MgSO4, filtered, and concentrated in vacuo. The resulting oil was

purified through silica gel chromatography (2:3 EtOAc:CH2Cl2) to afford compound 3.12

as a pale yellow oil (0.33 g, 88%). 1H NMR (CDCl3, 600 MHz): δ 8.48 (d, J=5.0, 1H),

3.77 & 3.67 (m, rotamers, 2H), 3.14 & 3.03 (m, rotamers, 3H), 3.09-3.03 (m, 2H). 13C NMR (CDCl3, 100 MHz): δ (159.7 & 159.5, rotamers), (154.9 & 154.6, rotamers),

(150.6 & 150.5, rotamers), 138.3, 137.2, 127.9, (121.7 &121.6, rotamers), (121.0 & 120.9, rotamers), (120.1 & 120.0, rotamers), 64.5, (48.9 & 48.3, rotamers), (36.5 & 36.0, rotamers), (35.9 & 35.5). FT-IR (νmax/cm−1): 2926, 2870, 1717, 1576, 1562, 1510.

HRMS: calcd [M]+ (C

16H18N2O3S2): 350.0759. Found (EI): 350.0768.

Synthesis of Compound 3.13. Compound 3.12 (0.25 g, 0.64 mmol, 1.0 equiv) was

dissolved in 4 mL of dry CH2Cl2. Pyridine (0.16 mL, 1.9 mmol, 2.0 equiv) and 4-

nitrophenyl chloroformate (0.26 g, 1.3 mmol, 2.0 equiv) were successively added to the reaction flask and the solution was stirred for 1.5 h at room temperature until completion as determined by TLC. The reaction mixture was diluted with CH2Cl2 and washed with

1M HCl followed by saturated NaHCO3. The organic layer was then dried over MgSO4,

filtered, and concentrated in vacuo. The resulting oil was purified through silica gel chromatography (CH2Cl2, then 1:9 EtOAc:CH2Cl2) to afford compound 3.13 as a pale

yellow oil (0.31 g, 92%). 1H NMR (CDCl3, 600 MHz): δ 8.46 (d, J=4.2, 1H), 7.70-7.59

(m, 2H), 7.45-7.39 (m, 2H), 7.35 (m, 2H), 7.15 (m, 2H), 7.13-7.07 (m, 2H), 5.25 (s, 2H), 3.77 & 3.66 (m, rotamers, 2H), 3.13 & 3.02 (m, roatmers, 3H), 3.08-3.03 (m, 2H).

13C NMR (CDCl

3, 100 MHz): (159.9 & 159.4, rotamers), 155.5, (154.5 & 154.2,

rotamers), 152.4, 151.9, (149.9 & 149.8, rotamers), 145.5, 137.1, 131.2, 130.0, 125.3, (122.1 &122.0, rotamers), 121.9, (121.0 & 120.9, rotamers), (120.1 & 120.0, rotamers), 70.4, (48.9 & 48.2, rotamers), (36.4 & 36.0, rotamers), (35.9 & 35.4, rotamers). FT-IR (νmax/cm−1): 3117, 3080, 3047, 2957, 2930, 1767, 1720, 1616, 1593, 1574, 1562, 1524.

HRMS: calcd [M]+ (C23H21N3O7S2): 515.0821. Found (EI): 515.0845.

Synthesis of Polymer 3.14. Activated monomer 2.1c19 (0.67 g, 1.3 mmol, 1.0 equiv) was

dissolved in 3 mL of 1:1 TFA:CH2Cl2 and stirred at room temperature for 2 h. The

solvent was then removed under a stream of nitrogen in the fume hood prior to subjecting the reaction mixture three times to a repeat cycle of dilution with CH2Cl2 followed by

concentration under reduced pressure to remove residual TFA and provide the

deprotected monomer 2.5.19 End-cap 3.13 (30 mg, 0.07 mmol, 0.05 equiv) was added and the resulting mixture was dissolved in 4.4 mL of anhydrous toluene and cooled to 0˚C.

NEt3 (0.92 mL, 6.6 mmol, 5.0 equiv) and DMAP (33 mg, 0.27 mmol, 0.2 equiv) were

sequentially added and the solution was stirred at 0˚C for 8h, let warm to room temperature, and stirred an additional 16 h. The solvent was then evaporated under reduced pressure and the crude polymer was dissolved in 2 mL of DMF and dialyzed against DMF for 24 h (200, mL, 1 solvent change) using a regenerated cellulose membrane (12000-14000 g/mol MWCO). The contents of the dialysis membrane were then concentrated in vacuo and lyophilized to afford polymer 3.14 (0.21 g, 60%). 1H

NMR indicated a degree of polymerization of ∼ 25 by integrating the benzylic peak against the thiopyridyl end-cap. 1H NMR (CDCl3, 400 MHz): δ 8.46 (d, J=5.3, 1H), 7.70-

7.59 (m, 2H), 7.40-7.27 (br, 48H), 7.11-6.99 (br, 50H), 5.14-5.01 (m, 48H), 3.62-3.37 (m, 94H), 3.75 & 3.65 (m, rotamers, 2H), 3.16-2.83 (m, 209H). SEC: Mn=3150g/mol,

Mw=5440g/mol, PDI=1.73 (PEG-PEO standards). Mn=5580g/mol, Mw=9720g/mol,

PDI=1.74 (PEG-PEO standards).

Synthesis of Polymer 3.16. Poly(ethylene glycol) thioacetate derivative (5000 g/mol)

3.1736,37 (20 mg, 4 µmol, 0.6 equiv) was dissolved in 2 mL of 1:2 freshly distilled

CH2Cl2:MeOH and cooled to 0˚C. Polymer 3.14 (30 mg, 7 µmol, 1.0 equiv) and NaOMe

(6 mg, 0.1 mmol, 16 equiv) were added and the solution was stirred at 0˚C for 8 h and then stirred an additional 8 h at room temperature. The crude reaction mixture was concentrated in vacuo and then dissolved in CH2Cl2 and washed with a 1:1 mixture of 1

M HCl:brine. The product was re-extracted from the aqueous layer an additional 5 times with CH2Cl2. The combined organic layers were dried over MgSO4, filtered, and

concentrated in vacuo. The crude product was dissolved in 2 mL of DMF and dialyzed against DMF for 24 h (200 mL, 1 solvent change) using a regenerated cellulose

membrane (12000-14000 g/mol MWCO). The contents of the dialysis membrane were then concentrated in vacuo and lyophilized to afford polymer 3.16 (37 mg, 57%). 1H NMR indicated a degree of polymerization of ∼ 28 by integrating the benzylic peak against the PEG end-cap. 1H NMR (CDCl

3, 600 MHz): δ 7.39-7.27 (br, 56H), 7.11-6.95

(br, 56H), 5.16-5.02 (m, 57H), 3.78-3.41 (m, 644H), 3.37 (s, 3H), 3.16-2.84 (m, 179H). SEC: Mn=5200g/mol, Mw=7330g/mol, PDI=1.41 (PEG-PEO standards).

Synthesis of Compound 3.18. Compound 3.1738(0.40 g, 2.9 mmol, 1.0 equiv) and NEt3

(0.70 mL, 9.5 mmol , 3.3 equiv) were added to 10 mL of dry CH2Cl2 cooled to 0˚C. 4-

Nitrophenyl chloroformate (0.65 g, 3.2 mmol, 1.1 equiv) dissolved in 5 mL of CH2Cl2

was added dropwise to the reaction mixture over 20 min. The solution was warmed to room temperature and stirred an additional 1.5 h until completion as determined by TLC. Freshly distilled triethylene glycol monomethyl ether (0.36 mL, 1.3 mmol, 0.45 equiv) was added and the reaction was stirred for 30 min to quench the remaining 4-nitrophenyl chloroformate. The reaction mixture was diluted with CH2Cl2 and washed with 1 M HCl.

The organic layer was dried over MgSO4, filtered, and concentrated in vacuo. The crude

solid was purified through silica gel chromatography (1:49 EtOAc:CH2Cl2) to afford 3.18

as a white solid (0.71 g, 80%). 1H NMR (CDCl3, 600 MHz): δ 8.28 (m, 2H), 7.45 (m,

2H), 7.37 (m, 2H), 7.23 (m, 2H), 4.44 (s, 2H), 3.37 (s, 3H). 13C NMR (CDCl3, 100 MHz): δ 155.3,151.0,150.1,145.6,128.9, 125.4, 121.8, 120.7, 73.9, 58.3. FT-IR (νmax/cm−1):

2928, 2854, 1763, 1726, 1618, 1595, 1526. HRMS: calcd [M]+ (C15H13NO6): 303.0743.

Found (EI): 303.0749.

Synthesis of Compound 3.19.Compound 3.9 was synthesized using the same procedure

outlined above. Compound 3.9 (0.24 g, 0.77 mmol, 1.5 equiv) and compound 3.18 (0.16 g, 0.51 mmol, 1.0 equiv)were dissolved in 5 mL of dry toluene. DIPEA (0.42 mL, 3.9 mmol, 5.0 equiv) and DMAP (20 mg, 0.15 mmol, 0.30 equiv) were successively added to the reaction flask and the solution was stirred at room temperature overnight. The

reaction mixture was then diluted with CH2Cl2 and washed with 1M HCl, followed by 1

M Na2CO3 and brine. The organic layer was dried over MgSO4, filtered, and concentrated

in vacuo. The resulting oil was purified through silica gel chromatography (3:20

EtOAc:CH2Cl2) to afford 3.19 as a pale yellow oil (0.13 g, 70%). 1H NMR (CDCl3, 600

MHz): δ 8.48 (d, J=5.3, 1H), 7.72-7.59 (m, 2H), 7.33-7.28 (m, 2H), 7.13-7.06 (m, 2H), 7.06-7.02 (d, J=8.0, 1H), 4.43 (s, 2H), 3.76 & 3.66 (m, rotamers, 2H), 3.36 (s, 3H), 3.14 & 3.02 (rotamers, 3H), 3.09-3.03 (m, 2H).13C NMR (CDCl

3, 100 MHz): δ (159.7 &

159.4, rotamers), (154.7 & 154.5, rotamers), 150.7, (149.8, & 149.7, rotamers), 137.1, 135.3, 128.6, 121.6, (121.0 & 120.9, rotamers), (120.0 & 119.9, rotamers), 74.1, (48.9 & 48.3, rotamers), (36.5 & 36.0, rotamers), (35.8, & 35.5, rotamers). FT-IR (νmax/cm−1):

2926, 2854, 2822, 1722, 1574, 1562, 1510. HRMS: calcd [M]+ (C17H20N2O3S2):

364.0915. Found (EI): 364.0916.

Synthesis of Compound 3.21.Compound 3.20 (0.14 g, 0.76 mmol, 1.5 equiv) and

compound 3.18 (0.15 g, 0.50 mmol, 1.0 equiv)were dissolved in 3 mL of dry toluene. DIPEA (0.26 mL, 1.5 mmol, 3.0 equiv) and DMAP (13 mg, 0.11 mmol, 0.21 equiv) were successively added to the reaction flask and the solution was stirred at room temperature overnight. The reaction mixture was then diluted with CH2Cl2 and washed with 1M HCl,

followed by 1 M Na2CO3 and brine. The organic layer was dried over MgSO4, filtered,

and concentrated in vacuo. The resulting oil was purified through silica gel

chromatography (3:20 EtOAc:CH2Cl2) to afford 3.20 as a pale yellow oil (0.16 g, 92%). 1H NMR (CDCl

3, 600 MHz): 7.32-7.28 (m, 2H), 7.10-7.05 (m, 2H), 4.42 (s, 2H), 3.61-

3.39 (m, methylenes, rotamers, 4H), 3.37-3.34 (m, 3H), 3.11 & 3.02 (rotamers, 3H), 2.94- 2.86 (m, rotamers, 3H), 1.50-1.40 (m, 9H).13C NMR (CDCl3, 100 MHz): δ (155.9, 155.7,

& 155.5, rotamers), (154.9 & 154.6, rotamers), (150.9 & 150.8, rotamers), (135.2 & 135.1, rotamers), 128.6, (121.8 & 121.6, rotamers), (79.9, 79.7, 79.6, & 79.5, rotamers), 74.1, 58.0, (47.4, 47.2, 47.0, 46.8, 46.6, 46.5, CH2 rotamers), (35.4 & 35.2, rotamers),

(34.7 & 34.6, rotamers), 28.4. FT-IR (νmax/cm−1): 2976, 2930, 1722, 1693, 1510. HRMS:

calcd [M]+ (C18H28N2O5): 352.1998. Found (EI): 352.1996.