LAT-1 activity of meta-substituted phenylalanine and tyrosine analogs
作者:Evan Augustyn、Karissa Finke、Arik A. Zur、Logan Hansen、Nathan Heeren、Huan-Chieh Chien、Lawrence Lin、Kathleen M. Giacomini、Claire Colas、Avner Schlessinger、Allen A. Thomas
DOI:10.1016/j.bmcl.2016.04.023
日期:2016.6
acid. Tyrosine and phenylalanineanalogs substituted at the meta position with halogens, alkyl and aryl groups were synthesized and tested in cis-inhibition and trans-stimulation cell assays to determine activity. Contrary to our initial hypothesis we found that lipophilicity was correlated with diminished substrate activity and increased inhibition of the transporter. The synthesis and SAR of meta-substituted
Approaches to the quaternary stereocentre and to the heterocyclic core in diazonamide A using the Heck reaction and related coupling reactions
作者:James E. M. Booker、Alicia Boto、Gwydion H. Churchill、Clive P. Green、Matthew Ling、Graham Meek、Jaya Prabhakaran、David Sinclair、Alexander J. Blake、Gerald Pattenden
DOI:10.1039/b609604b
日期:——
In model studies towards the quaternary centre at the heart of diazonamide A (early structure 2; revised structure 1), cyclisations of the alkene-substituted iodoaryls 4, 13, 18 and 23, under Heck reaction conditions, were shown to lead to the corresponding benzodihydrofuran 5, benzofuranone 14 and the oxindoles 19 and 24 respectively, in 50–80% yield. Further manipulation of the benzodihydrofuran 5 then led to the intermediates 30, 33 and 39, which make up parts of the oxazole–indole heterocyclic core in diazonamide A. Attempts to perform a corresponding 13-exo-trig Heck cyclisation from the precursor 46a, prepared from 44 and 45, leading to 47 were not successful. A similar outcome was obtained during attempts to effect Heck cyclisations from the ester 57 and the related ether 59. Treatment of the chromene-substituted iodoaryl 62 with Pd(OAc)2, PPh3 and Ag2CO3 led to the spirocycle 64 as a crystalline solid. X-Ray crystal structure analysis established that the quaternary centre in 64 had the same configuration as that present in diazonamide A (1).
作者:Xu Zhu、Christopher C. McAtee、Corinna S. Schindler
DOI:10.1021/jacs.8b13849
日期:2019.2.27
An approach for the syntheses of herqulines B and C is reported that takes advantage of an l-tyrosine-derived diketopiperazine, a mycocyclosin analogue, as a synthetic precursor. The strategy relies on a series of consecutive reductions to adjust the mycocyclosin oxidation state to that observed in the herquline class of natural products. The strained and distorted l-tyrosine-based biaryl system characteristic
据报道,一种合成 Herqulines B 和 C 的方法利用 l-酪氨酸衍生的二酮哌嗪(一种霉菌环素类似物)作为合成前体。该策略依赖于一系列连续的还原来将霉菌环素氧化状态调整为在天然产物 Herquline 类中观察到的状态。通过初始高价碘介导的脱芳构化和随后的定向桦木还原,通过分子内 H-来源。此外,哌嗪氧化态可通过二酮哌嗪中间体的铁催化还原获得。
Development of a Potent Thrombin Receptor Ligand
作者:Dong-Mei Feng、Daniel F. Veber、Thomas M. Connolly、Cindra Condra、Mei-Jy Tang、Ruth F. Nutt
DOI:10.1021/jm00020a029
日期:1995.9
The N-terminal thrombin receptor peptide H-Ser-Phe-Leu-Leu-Arg-Asn-Pro-Asn-Asp-Lys-Tyr-Glu-Pro-Phe-OH (1) fully activates the thrombin receptor with an EC(50) Of 10 mu M Structural features in the tetradecapeptide which are responsible for receptor activation have been elucidated. Agonist potency has been enhanced 1000-fold with the design of the shortened peptide H-Ala-Phe(p-F)-Arg-Cha-HArg-Tyr-NH2 (56). This analog exhibits an EC(50) of 0.01 mu M and is the most potent agonist for receptor activation reported to date. The monoiodinated derivative H-Ala-Phe(p-F)-Arg-Cha-HArg-Tyr(3-I)-NH2 (59) exhibits an EC(50) of 0.03 mu M, a level sufficient for development of a radioligand.
Total Synthesis of Nominal Diazonamides-Part 1: Convergent Preparation of the Structure Proposed for (−)-Diazonamide A
作者:Jing Li、Susan Jeong、Lothar Esser、Patrick G. Harran