Shaojun Zheng

Publications (3)13.85 Total impact

• Article: Synthesis and biological profiling of tellimagrandin I and analogues reveals that the medium ring can significantly modulate biological activity.

  Shaojun Zheng, Luca Laraia, Cornelius J O' Connor, David Sorrell, Yaw Sing Tan, Zhaochao Xu, Ashok R Venkitaraman, Wenjun Wu, David R Spring
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  ABSTRACT: A novel synthesis of the ellagitannin natural product tellimagrandin I and a series of medium ring analogues is described. These compounds were all subsequently screened for redox activity, ability to precipitate protein and cellular phenotype in HeLa cells. From this we have shown that all properties can be modulated independently by varying ring size and by moving the ester out of conjugation with the biaryl ring system. Increasing ring size increased redox activity and cytotoxicity, leading to the identification of a compound (10) which was significantly more cytotoxic. In addition compounds identified with a redox active scaffold and low cytotoxicity may be employed as a new class of redox probes.
  Organic & Biomolecular Chemistry 04/2012; 10(13):2590-3. · 3.70 Impact Factor
• Article: A concise total synthesis of deoxyschizandrin and exploration of its antiproliferative effects and those of structurally related derivatives.

  Shaojun Zheng, Sarah J Aves, Luca Laraia, Warren R J D Galloway, Kurt G Pike, Wenjun Wu, David R Spring
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  ABSTRACT: The natural product deoxyschizandrin has been shown to have a wide range of biological activities. In recent years the therapeutic potential of this compound against cancers has attracted significant interest. Herein we describe a concise de novo total synthesis of deoxyschizandrin based around a double organocuprate oxidation strategy. In addition, we present the results of biological studies exploring the ability of deoxyschizandrin and synthetic precursors lacking the medium ring biaryl unit to inhibit the proliferation of a human cancer cell line. These studies led to the identification of a structurally novel agent with in vitro anticancer activity.
  Chemistry 03/2012; 18(11):3193-8. · 5.93 Impact Factor
• Source

  Available from: cam.ac.uk

  Article: Discovery of a highly selective turn-on fluorescent probe for Ag+.

  Zhaochao Xu, Shaojun Zheng, Juyoung Yoon, David R Spring
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  ABSTRACT: An ideal fluorescent probe should show the strongest affinity with the relevant target (binding-selectivity) by means of a selective fluorescence change (signal-selectivity). [15]aneNO(2)S(2) (1,4-dioxa-7,13-dithia-10-azacyclopentadecane) based probes usually show high binding selectivity for Ag(+) but signal selectivity for Hg(2+), because Ag(+) can quench or silence the fluorescence. To amplify the Ag(+) binding to the greatest extent, a carbonyl group was positioned between 1,8-naphthalimide and [15]aneNO(2)S(2) which played a key role of displaying selective fluorescence enhancements with Ag(+) through increasing the oxidation potential of the fluorophore, blocking Ag(+) from sterically interacting with the naphthalimide fluorophore, and by acting as a sacrificial donor. Probe 2 can detect Ag(+) with a selective fluorescence enhancement (∼14 fold) and high affinity (K(a) = 1.64 × 10(5) M(-1)).
  The Analyst 10/2010; 135(10):2554-9. · 4.23 Impact Factor