155645-89-9Relevant articles and documents
Asymmetric Total Synthesis and Biosynthetic Implications of Perovskones, Hydrangenone, and Hydrangenone B
Gao, Shuanhu,He, Haibing,Hou, Min,Wen, Guoen,Yang, Baochao,Zhang, Quan
supporting information, p. 6370 - 6375 (2021/05/31)
Perovskones and hydrangenones are a family of structurally complex triterpenoids that were mainly isolated from the genus Salvia medicinal plants. These isoprenoids exhibit a broad range of biological activities, such as antitumor and antiplasmodial activities. Here, we report the collective total synthesis of perovskone, perovskones C, D, F, hydrangenone, and hydrangenone B. The key strategies in this work include the following: (1) an asymmetric photoenolization/Diels-Alder reaction was developed to construct a tricyclic ring bearing three contiguous quaternary centers, which was used to build the core icetexane skeleton; (2) a bioinspired Diels-Alder reaction of perovskatone D with trans-α-ocimene was applied to stereospecifically generate perovskones; (3) late-stage oxidations and ring forming steps were developed to synthesize perovskones and hydrangenones. Our synthetic work suggests that (1) perovskatone D may serve as the precursor of the biosynthesis of perovskones and (2) the formation of hydrangenone and hydrangenone B, containing a five-membered D ring, may involve an oxidative ring cleavage and ring regeneration process.
Coordination chemistry of Cu(II), Co(II), Zn(II) and Ag(I) complexes of isomeric pyridine 2- and 4-carboxamides and their biological activity evaluation
Lumb, Isha,Sran, Balkaran Singh,Sood, Henna,Arora, Daljit Singh,Hundal, Geeta
, p. 153 - 166 (2017/03/09)
Eight complexes of Cu(II), Co(II), Zn(II) and Ag(I) with rarely studied ligands, N,N-diisopropyl/butylpicolinamide (L1/L2), and N,N-diisopropyl/butylisonicotinamide (L3/L4), have been synthesized and characterized spectroscopically, and their molecular and crystal structures have been reported. Diverse coordination modes of these positional isomers have been discovered, discussed and compared with the limited available literature in light of their respective convergent and divergent nature. All the complexes show stable and extended 1D, 2D or 3D coordination/H-bonded networks owing to a large number of weak C–H?O/X and other intermolecular interactions. Further, the ligands as well as the metal complexes have been evaluated for their antimicrobial activity and have turned out to be potent antimicrobial agents.
The super-iron boride battery
Licht, Stuart,Yu, Xingwen,Wang, Yufei,Wu, Huiming
, p. A297-A303 (2009/01/31)
A high-capacity alkaline redox storage chemistry is explored based on an environmentally benign zirconia-stabilized Fe6+ B2- chemistry. This super-iron boride battery sustains an electrochemical potential matched to the pervasive, conventional MnO2 -Zn battery chemistry, but with a much higher electrochemical storage capacity. Whereas a conventional alkaline battery pairs the 2 e- zinc anode with a 1 e- MnO2 cathode, the new alkaline cell couples an 11 e- boride anode, such as VB2, with a 3 e- storage hexavalent iron cathode. The cell has an open circuit and discharge potential comparable to the conventional, commercial alkaline battery. Based on VB2 (72.6 g mol-1) and the Fe(VI) salt K2 FeO4 (198.0 g mol-1), the super-iron boride cell has an 11 Faraday theoretical capacity of 369 mAh g-1. Added AgO mediates and further facilitates the 3 e- K2 FeO4 reductive charge transfer, and we demonstrate for super-iron boride that over 300 mAh g-1 is approached experimentally, which is substantially higher than the conventional Zn MnO2 alkaline battery with an experimental capacity (to 0.8 V) of 160 mAh g-1 and a theoretical capacity of 224 mAh g-1.
