| 4 | Orientational Chirality,Its Asymmetric Control,and Computational Study显示文摘Orientational chirality was discovered and characterized by a C(sp)-C(sp3)axis-anchored chiral center and a remotely anchored blocker.X-ray structural analysis proved that orientatiomers are stabilized by through-space functional groups,making it possible for 1 R-or S-chiral center to exhibit 3 orientational isomers simply by rotating operations.A new model system was proposed,fundamentally different from the traditional Felkin-Ahn-type or Cram-type models.In these traditional models,chiral C(sp^(3))center and blocking C(sp^(3))carbons are connected adjacently,and there exist 6 energy barriers during rotating along the C(sp^(2))-C(sp^(3))axis.In comparison,the present orientational chirality model shows that a chiral C(sp)-C(sp^(3))carbon is remotely located from a blocking group.Thus,it is focused on the steric dialog between a chiral C(sp^(3))center and a remotely anchored functional group.There exist 3 energy barriers for either(R)-or(S)-C(sp)-C(sp^(3))stereogenicity in the new model.Chiral amide auxiliary was proven to be an excellent chiral auxiliary in controlling rotations of orientatiomers to give complete stereoselectivity.The asymmetric synthesis of individual orientatiomers was conducted via multistep synthesis by taking advantage of the Suzuki-Miyaura cross-coupling and Sonogashira coupling reactions.Density functional theory computational study presented optimized conformers and relative energies for individual orientatiomers.This discovery would be anticipated to result in a new stereochemistry topic and have a broad impact on chemical,biomedical,and material sciences in the future. | Shengzhou Jin Yu Wang Yao Tang Jia-Yin Wang Ting Xu Junyi Pan Sai Zhang Qiankai Yuan Anis Ur Rahman James D.McDonald Guo-Qiang Wang Shuhua Li Guigen Li | 2023 | Research2023，，1： | 0 |
| 5 | Hepatic and renal effects of oral stingless bee honey in a streptozotocin-induced diabetic rat model显示文摘BACKGROUND Diabetes is known damage the liver and kidney,leading to hepatic dysfunction and kidney failure.Honey is believed to help in lowering the blood glucose levels of diabetic patients and reducing diabetic complications.However,the effect of stingless bee honey(SBH)administration in relieving liver and kidney damage in diabetes has not been well-studied.AIM To investigate the effect of SBH administration on the kidney and liver of streptozotocin-induced(STZ;55 mg/kg)diabetic Sprague Dawley rats.METHODS The rats were grouped as follows(n=6 per group):non-diabetic(ND),untreated diabetic(UNT),metformin-treated(MET),and SBH+metformin-treated(SBME)groups.After successful diabetic induction,ND and UNT rats were given normal saline,whereas the treatment groups received SBH(2.0 g/kg and/or metformin(250 mg/kg)for 12 d.Serum biochemical parameters and histological changes using hematoxylin and eosin(H&E)and periodic acid–Schiff(PAS)staining were evaluated.RESULTS On H&E and PAS staining,the ND group showed normal architecture and cellularity of Bowman’s capsule and tubules,whereas the UNT and MET groups had an increased glomerular cellularity and thickened basement membrane.The SBH-treated group showed a decrease in hydropic changes and mild cellularity of the glomerulus vs the ND group based on H&E staining,but the two were similar on PAS staining.Likewise,the SBME-treated group had an increase in cellularity of the glomerulus on H&E staining,but it was comparable to the SBH and ND groups on PAS staining.UNT diabetic rats had tubular hydropic tubules,which were smaller than other groups.Reduced fatty vacuole formation and dilated blood sinusoids in liver tissue were seen in the SBH group.Conversely,the UNT group had high glucose levels,which subsequently increased MDA levels,ultimately leading to liver damage.SBH treatment reduced this damage,as evidenced by having the lowest fasting glucose,serum alanine transaminase,aspartate transaminase,and alkaline phosphatase levels compared to other groups,although the levels of liver enzymes were not statistically significant.CONCLUSION The cellularity of the Bowman’s capsule,as well as histological alteration of kidney tubules,glomerular membranes,and liver tissues in diabetic rats after oral SBH resembled those of ND rats.Therefore,SBH exhibited a protective hepatorenal effect in a diabetic rat model. | Suriati Mohd Nasir Anis Farihan Ismail Tuan Salwani Tuan Ismail Wan Faiziah Wan Abdul Rahman Wan Amir Nizam Wan Ahmad Tengku Ahmad Damitri Al-Astani Tengku Din Kuttulebbai Nainamohammed Salam Sirajudeen | 2024 | World Journal of Experimental Medicine2024，14，1： | 0 |
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