N-(Triphenylmethyl)-L-asparagine

White to off-white powder

The cyclic CD2O mimotope for Rituximab binding was synthesized using standard solid phase synthesis protocols on a NovaPEG Rink Amide resin and Fmoc chemistry. The following residues were HBTU activated and coupled following Fmoc deprotection in the following order: Cys (Trt), Met, Ser(tBu), Pro, Asn(Trt), Ala, Ala, Trp(Boc), Cys (Trt), Ala, and N-amido-dPEG2-acid. Kaiser tests were performed between coupling steps to monitor synthesis progress. The peptide was cleaved from the resin in 92.5% TFA, 2.5% TIS, 2.5% EDT, and 2.5% DI. water, purified via RP-HPLC on a Zorbax C18 column, and characterized using MALDI-TOF MS (FIG. 10). The yield was 50%, and product purity was confirmed using RP-HPLC on an analytical Zorbax Ci 8 column to be >95%. The peptide was cyclized overnight in DMF with DIEA and verified via MALDI-TOF MS.Example 11General Procedure for the Preparation of 5, 6-Dimethoxy-l, l- dioxobenzo[Z>]thiophene-2-methoxycarbonyl Amino Acids Using Dmoc-OSu in Acetonitrile-Water in the Presence of Triethylamine. Method ATo a suspension of 39.02 mmol of an amino acid in 400 mL of acetonitrile/water (1/1) was added an amount of triethylamine to give an apparent pH of 9 (approximately 12 mL). The suspension became clear. The pH was kept at 8.5-9.0, after the addition of 5, 6-DM-Bsmoc-OSu (15.5 g, 39.02 mmol), by adding triethylamine. The uptake of base ceased after about 15 min after which the reaction mixture was stirred at room temperature for 40-45 min and concentrated in vacuo. The mixture was diluted with about 75 mL of water and acidified to pH 2 with 0.1 N HC1 and the resulting oil was dissolved in ethyl acetate (300 mL). The EtOAc was washed with saturated NaCl solution (2 x 100 mL), dried over MgS04, filtered and the solvent was evaporated in vacuo to give the solid amino acids, the properties of which are given below. Evaporation of ethyl acetate and then recrystallization from hot ethyl acetate gave 17.94 g (70.0%) of the acid as a white solid, m.p. 215-220 C; 1H NMR (DMSO-d6): delta 2.68 (d, 2), 3.8 (d, 6), 4.29 (q, 1), 4.98 (q, 2), 6.96-7.27 (m, 16+), 7.39 (s, 1), 7.55 (s, 1), 7.72 (d, 1, NH), 8.64 (s, 1). Anal. Calcd for C35H32N209S: C, 64.01; H, 4.91; N: 4.27. Found: C, 63.72; H, 4.99; N, 4.25.

Molecular Weight:374.4
XLogP3:1.2
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:6
Exact Mass:374.16304257
Monoisotopic Mass:374.16304257
Topological Polar Surface Area:96.9
Heavy Atom Count:28
Complexity:467
Defined Atom Stereocenter Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes