Diisopropylethylamine → (S)-tert-butyl 2-((S)-2-(4-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzamido)-3-methylbutanamido)propanoate

Participants

Role	Name	HCID	Charge
Reactant	Diisopropylethylamine	HCID 81531	—
Reactant	4-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)benzoic acid	HCID 86925	—
Reactant	O-(Benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate	HCID 2733207	—
Reactant	tert-butyl (2S)-2-[(2S)-2-amino-3-methylbutanamido]propanoate	HCID 86676194	—
Solvent	Dichloromethane	HCID 6344	—
Product	(S)-tert-butyl 2-((S)-2-(4-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzamido)-3-methylbutanamido)propanoate	HCID 67451966	52.2%

Reaction Steps

To a mixture of the 97 (100 mg, 0.41 mmol) and 4-maleimidobenzoic acid (101) (98 mg, 0.45 mmol) was added dichloromethane (5 mL), followed by TBTU (157 mg, 0.49 mmol) and DIPEA (212 uL, 1.23 mmol). The mixture was stirred at an ambient temperature for 16 h and then purified on a 2 mm radial chromatotron plate eluting with 50% ethyl acetate in hexanes to give 95 mg (51%) of 100: 1H-NMR (400 MHz, CDCl3) δ 7.85 (d, J=6.6 Hz, 2H), 7.42 (d, J=6.6 Hz, 2H), 6.81 (s, 2H), 6.38 (bs, 1H), 4.43 (m, 2H), 2.14 (sept, J=6.6 Hz, 1H), 1.41 (s, 9H), 1.31 (d, J=7.0 Hz, 3H), 0.98 (m, 6H); MS (ES−) m/z 441.90 [M−H]−.

Provenance & Evidence

DOI	10.6084/m9.figshare.5104873.v1
Patent number	US09242013B2
Source dataset	uspto-grants-2016_01
ORD ID	ord-55bea4ea74de4fee8833c60ac9136044
Source note	uspto-grants-2016_01