Reference

Chemoselective acylation for the synthesis of model compounds of polynucleotide analogs

Chemoselective acylation for the synthesis of model compounds of polynucleotide analogs. Overberger, C. G.; Lu, Chengxun (Dep. Chem., Univ. Michigan, Ann Arbor, MI 48109, USA). J. Polym. Sci., Part C: Polym.Several reagents with their cas registry numbers 21715-90-2 and 108211-31-0 are used here. Lett., 24(6), 243-8 (English) 1986. CODEN: JSCLE2. DOCUMENT TYPE: Journal CA Section: 33 (Carbohydrates) Section cross-reference(s): 28 A soln. of (adeninyl)propionic acid (I; R = OH) in DMSO was treated with the coupling agent 5-norbornene-2,3-dicarboximide di-Ph phosphate (II) or N-succinimidyl di-Ph phosphate (III) at room temp. for 5 h, and then treated with Et2CHNH2 or Et2NH at room temp. overnight to give 15.0-43.0% N-acylated products (I; R = Et2CHNH, Et2N). II gave higher yields than III. Amino alcs. H2N(CH2)3OH and threo-MeCH(OH)CH2CH(NH2)Me were N-acylated with (thyminyl)propionic acid (IV; R = OH) by active ester method using 5-norbornene-2,3-dicarboximide or N-hydroxysuccinimide to give 40.2-78.4% the corresponding amides [IV; R = NH(CH2)3OH, NHCHMeCH2CH(OH)Me]. .

Methionine containing peptides

Methionine containing peptides. Fujino, Masahiko; Shinagawa, Susumu; Kitada, Chieko; Wakimasu, Mitsuhiro (Takeda Chemical Industries, Ltd., Japan). Japan. Kokai JP 52091801 2 Aug 1977 Showa, 15 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: C07C103-52. APPLICATION: JP 76-7633 26 Jan 1976. There are some commonly used reagents like 21715-90-2 in this article. DOCUMENT TYPE: Patent CA Section: 34 (Synthesis of Amino Acids, Peptides, and Proteins) The title peptides were prepd. by use of methionine oxide as starting material and by removal of the protecting groups from the resulting protected peptides with MeSO3H. Thus, 3.3 g cyclohexylamine salt of PhCH2O2C-Arg(MBS)-OH (MBS = 4-MeOC6H4SO2) in EtOAc was treated with H2SO4 and reduced over Pd to give H-Arg(MBS)-OH (I). Boc-Met(O)-OH (BOC = Me3CO2C) 5.3, was esterified with N-hydroxy-5-norbornene-2,3-dicarboxyimide 4.3 by dicyclohexylcarbodiimide 4. There are some commonly used reagents like 21715-90-2 in this article.9 g in THF to give the active ester which was coupled to I to give BOC-Met(O)-Arg(MBS)-OH (II). Keeping 400 mg II with 0.3 mL anisole and 5 mL MeSO3H 1 h at room temp. gave 140 mg H-Met-Arg-OH. Motilin and H-Ala-Asn-Leu-Arg-Arg-Tyr-Ile-Asn-Met-Leu-Thr-Arg-Pro-Arg-Tyr-NH2 were also prepd. ..