1.Synthesis of [(11)C]GSK1482160 as a new PET agent for targeting P2X(7) receptor.
Gao M;Wang M;Green MA;Hutchins GD;Zheng QH Bioorg Med Chem Lett. 2015 May 1;25(9):1965-70. doi: 10.1016/j.bmcl.2015.03.021. Epub 2015 Mar 14.
The authentic standards GSK1482160 and its isomer, as well as the radiolabeling precursors desmethyl-GSK1482160 and Boc-protected desmethyl-GSK1482160 were synthesized from L-pyroglutamic acid, methyl L-pyroglutamate and 2-chloro-3-(trifluoromethyl)benzylamine with overall chemical yield 27-28% in 3 steps, 58% in 4 steps, 76% in 1 step and 33% in 2 steps, respectively. [(11)C]GSK1482160 was prepared from either desmethyl-GSK1482160 or Boc-protected desmethyl-GSK1482160 with [(11)C]CH3OTf through N-[(11)C]methylation and isolated by HPLC combined with SPE in 40-50% and 30-40% radiochemical yield, respectively, based on [(11)C]CO2 and decay corrected to end of bombardment (EOB). The radiochemical purity was >99%, and the specific activity at EOB was 370-1110 GBq/μmol with a total synthesis time of ∼40-min from EOB.
2.Application of intramolecular enyne metathesis to the synthesis of aza[4.2.1]bicyclics: enantiospecific total synthesis of (+)-anatoxin-a.
Brenneman JB;Martin SF Org Lett. 2004 Apr 15;6(8):1329-31.
A concise synthesis of the potent nAChR agonist (+)-anatoxin-a (1) has been completed in a series of only nine chemical operations and 27% overall yield from commercially available D-methyl pyroglutamate (4). The synthesis features a novel procedure for the diastereoselective preparation of cis-2,5-disubstituted pyrrolidines leading to 10, which underwent an intramolecular enyne metathesis to afford a bridged azabicyclic intermediate that was transformed into 1. [reaction: see text].
3.[Chemical constituents from Hydrangea macrophylla].
Wang ZB;Guo JT;Yang CJ;Meng YH;Wang QH;Yang BY;Kuang HX Zhongguo Zhong Yao Za Zhi. 2013 Mar;38(5):709-13.
OBJECTIVE: ;To investigate chemical constituents from Chinese herbal medicine Hydrangea macrophylla.;METHOD: ;The compounds were separated and purified by column chromatography over silica gel, ODS, and preparative HPLC. Their structures were identified by spectral methods including 1H, 13C-NMR and MS.;RESULT: ;Eleven compounds were isolated and identified as zeorin, hopane-6, 22-diol (1), botulin (2), betulinic acid (3), 2-ethyl-3-methyl-maleimide-N-beta-D-glucopyranoside (4), uridine (5), thymidine (6), adenosine (7), nicotinamide (8), methyl pyroglutamate (9), hydrangenol (10) and hydrangenol-4'-O-beta-D-glucopyranoside (11), respectively.;CONCLUSION: ;Compounds 14 and 7-9 were obtained from the genus Hydrangea for the first time.
