Efficient synthesis of 2,5-diketopiperazines using microwave assisted heating
作者:Marcus Tullberg、Morten Grøtli、Kristina Luthman
DOI:10.1016/j.tet.2006.05.010
日期:2006.7
In this study a general, efficient and environmentally benign solution phase synthesis of 2,5-diketopiperazines (DKPs) using microwave assisted heating in water is described. A series of 11 structurally different DKPs have been synthesized from dipeptide methyl esters. A range of common laboratory solvents have been tested as well as different reaction times and temperatures. Both classic thermal and
General solvent-free highly selective N-tert-butyloxycarbonylation strategy using protic ionic liquid as an efficient catalyst
作者:Swapan Majumdar、Jhinuk De、Ankita Chakraborty、Dilip K. Maiti
DOI:10.1039/c4ra02670e
日期:——
transformation of amines to tert-butyloxycarbonyl protected derivatives (NHBoc) using Boc2O and imidazolium trifluoroacetate protic ionic liquid (5–20 mol%). Unwanted side products such as isocyanate, urea or N,N-di-Boc were not detected. The scope of the protection strategy was successfully explored for substrate alcohols, phenols and thiol at elevated temperatures. Optically pure amino acids, amino acid esters
[EN] BIOREVERSABLE PROMOIETIES FOR NITROGEN-CONTAINING AND HYDROXYL-CONTAINING DRUGS<br/>[FR] PRO-FRAGMENTS BIORÉVERSIBLES POUR MÉDICAMENTS CONTENANT DE L'AZOTE ET DE L'HYDROXYLE
申请人:BAIKANG SUZHOU CO LTD
公开号:WO2015081891A1
公开(公告)日:2015-06-11
Disclosed are promoieties of the following formula which can be used to form prodrugs of nitrogen-containing or hydroxyl-containing drug or a pharmaceutically active agent: (I) and pharmaceutical compositions comprising the prodrugs.
Substituted uracil derivatives of formula (I), processes for their preparation, their use alone or in combinations for the treatment and/or prophylaxis of diseases, and their use for preparing medicaments for the treatment and/or prophylaxis of diseases.
Synthesis of a Derivative of the Peptaibol-Antibiotic Trichovirin I 1B by Means of the‘Azirine/Oxazolone Method’
作者:Roeland T. N. Luykx、Anthony Linden、Heinz Heimgartner
DOI:10.1002/hlca.200390339
日期:2003.12
Aib residues were introduced by the coupling of the corresponding amino or peptide acids with 2,2-dimethyl-2H-azirine-3-(N-methyl-N-phenylamine) (1a) and methyl N-(2,2-dimethyl-2H-azirin-3-yl)-L-prolinate (3a) as the Aib and Aib-Prosynthons, respectively. Single crystals of two segments, i.e., the N-terminal hexapeptide Z-Aib-Asn(Trt)-Leu-Aib-Pro-Ser(tBu)-OMe (23) and the C-terminal octapeptide Z-V
根据Trichovirin I 1B,Z-Ser(t Bu)-Val-Aib-Pro-Aib-Leu-Aib-Pro-Leuol(5)的C端九肽的较早合成方法,完整的四肽Z-Aib -Asn(Trt)-Leu-Aib-Pro-Ser(t Bu)-Val-Aib-Pro-Aib-Leu-Aib-Pro-Leuol(11b)是一种受保护的Trichovirin I 1B,目前已通过以下方法制备“叠氮基/恶唑酮法”。除了N末端Aib(1)以外,所有Aib残基都是通过相应的氨基酸或肽酸与2,2-二甲基-2 H -azirine-3-(N-甲基-N-苯胺)偶联而引入的)(1a)和甲基N-(2,2-二甲基-2 H-Azirin-3-基)-L-脯氨酸盐(3a)分别作为Aib和Aib-Pro合成子。两段,单晶即,N末端六肽Z-AIB-的Asn(TRT)-Leu-AIB -脯氨酸-丝氨酸(吨丁基)-OMe(