, 25 mmol), HOBt (1.72 g, 11.25 mmol), Fmoc-Ala-OH (2.34 g, 7.5 mmol) and DIPEA, p.61

, 3 mL) was added. The amino acid resin mixture was agitated for 4 h. The solution was then drained and washed with DMF (30 mL), isopropanol (30 mL) and n-hexane (30 mL). 2,2,2-Trifluroethanol in CH2Cl2 (15 mL, 1:4) was added to the amino acid-loaded resin and agitated for 2 h. The solution was drained and the organic solvent, p.22

, ºC, g, 78%) as a yellow foam, pp.195-196

, MeOH, vol.53, issue.1, p.9

, H NMR (CHCl3, 500 MHz) ? 8.09 (1H, d, J = 7.2 Hz, NH-5), 7.89 (2H, d, J = 7.4 Hz, 2H-FmocAr), 7.74 (1H, d, J = 7.4 Hz, 1H-FmocAr), 7.72 (1H, d, J = 7.4 Hz, 1H-FmocAr), 7.50 (1H, d, J = 7.5 Hz, NH-1), 7.41 (2H, t, J = 7.4 Hz, H-FmocAr), vol.3297, pp.1229-1230, 1318.

, 143.8 (C-FmocAr), 140.7 (2C-FmocAr), vol.143

, 7 (CO2CH2CH), vol.46

-. Fmoc, , vol.22, pp.8-58

, A solution of 4 HF3.1 (0.135 g, 0.461 mmol) in DMF (1.5 mL) was added to the mixture followed by DIPEA (0.40 mL, 2.30 mmol). The solution was stirred at r.t. under N2 for 7 h. The solution was diluted with EtOAc (10 mL) and washed with water (5 mL). The organic layer was dried (MgSO4), filtered and the solvent removed in vacuo. The crude product was purified by silica gel flash column chromatography, HOBt (0.093 g, 0.691 mmol) was dissolved in DMF (1.5 mL) and the mixture was stirred for 1 h at r.t. under N2

. Fmocar, 2CFmocAr), 2C-FmocAr and C-21), 118.7 (C-13), vol.127

, 42.3 (C-10), vol.18

, mmol) was added piperidine (20% in DMF, 1 mL) and flushed with nitrogen. The solution was stirred at r.t. for 20 min before EtOAc (20 mL) was added and the mixture was washed with water (10 mL). The aqueous layer was further washed with EtOAc (3 ? 10 mL) and the organic layers were combined and dried in vacuo. Purification by silica gel column chromatography (eluting with EtOAc to CH2Cl2, vol.24, pp.8-100

D. , MeOH, issue.6

, IR (ATR) ?max 3393, 2258, 1655, 1048, 1024 cm-1 ; 1 H NMR (DMSO-d6, 300 MHz) ? 11.49 (1H, br s, NH-17), vol.9, p.11

(. 1h, D. , and J. =. , 1H, br s, NH-5), 7.70 (1H, s, H16), 7.58 (1H, d, J = 1.8 Hz, H-18), 7.56 (1H, d, J = 8.4 Hz, H-21), vol.7

, 13 C NMR (DMSO-d6, 75 MHz) ? 175.1 (C-4), vol.9, pp.167-172

, C-16), C-17a), 125.6 (C-21a), vol.124

, C-14), vol.102, pp.109-116

, The synthesis of 23 HF8-86 used Fmoc-D-Ala-OH and the same procedure as described for the synthesis of Fmoc-L-Ala-L-Ala-OH (22 HF8-58), to give the product (0.45 g, 79%) as a white solid, vol.9, pp.196-197

D. , MeOH, vol.35

, IR (ATR) ?max 3293, pp.1262-1263, 1319.

1. Hz, D. , and J. =. , 1H-FmocAr), 7.50 (1H, d, J = 7.5 Hz, NH-1), 7.41 (2H, t, J = 7.4 Hz, H-FmocAr), 7.32 (2H, td, J = 7.4, 0.9 Hz, 2H-FmocAr

. Hz, , vol.143, pp.3-3

, 143.8 (C-FmocAr), 140.7 (2C-FmocAr), vol.127

(. , , vol.18

-. Fmoc,

, 399 mmol) were dissolved in DMF (1.5 mL) and stirred at r.t. for 1 h under nitrogen

, 266 mmol) in DMF (1.5 mL) was then added followed by DIPEA (0.23 mL, 1.33 mmol). The solution was further stirred at r.t. for 7 h. EtOAc (10 mL) was added to the mixture and washed with water (5 mL). The organic layer was dried (MgSO4), filtered and the solvent removed in vacuo. The crude product was purified by silica gel flash column chromatography, vol.60, p.0

. Mg, 34%) as a yellow oil

, NH-12), 8.14 (1H, d, J = 5.8 Hz, NH-9, H NMR (DMSO-d6, 300 MHz) ? 11.43 (1H, s, NH-17), 9.13 (1H, d, J = 9.9 Hz, vol.3367, pp.1130-1131, 1231.

, = 9.9, 9.7 Hz, H-13), 5.91 (1H, d, J = 9, vol.172, pp.3-3

, 2CFmocAr), 124.8 (C-16), 167.4 (C-11), 155.7 (CO2CH2CH), vol.143

, 42.3 (C-10), vol.18

. Piperidine, 52 mmol) and stirred at r.t. under N2 for 20 min. EtOAc (20 mL) was added and the mixture was washed with water (10 mL). The aqueous layer was further washed with EtOAc (3 ? 10 mL) and the organic layers were combined and dried in vacuo. Purification by silica gel column chromatography (eluting with EtOAc to CH2Cl2, vol.8, pp.8-136

, CH2Cl2

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