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21.
Yoshitane Imai Kakuhiro Kawaguchi Tomohiro Sato Michiya Fujiki Yoshio Matsubara 《Tetrahedron letters》2007,48(16):2927-2930
By using (1R,2R)-1,2-diphenylethylenediamine as a chiral molecule and 2-anthracenecarboxylic acid as a fluorescent molecule, we created a chiral supramolecular organic fluorophore having circularly polarized luminescence properties in the solid-state. 相似文献
22.
Because Nitrosomonas europaea contains ammonia-oxidizing enzyme, nitrite reductase, and nitrous oxide reductase, the conversion of ammonia to dinitrogen
was tried with different reaction conditions. In aerobic reaction conditions, ammonium was converted to nitrite (NO
2
−
), while under oxygen-limiting or oxygen-free conditions, NO
2
−
-N formed from ammonia oxidation by N. europaea was reduced to N2O and dinitrogen with 22% conversion. During denitrification, optimal pH for the production of N2O and dinitrogen was found to be 7.0–8.0. Dinitrogen was not produced in acidic pH<7.0. A low partial oxygen pressure as well
as oxygen-free conditions are favorable for high production of dinitrogen. 相似文献
23.
Allylation of carbonucleophiles with allylic carbamates under neutral conditions has been studied. The C-allylation of carbonucleophile is competitive with the N-allylation of amines, and the structure of amines is crucial for the selectivity. Bulky secondary amines gave the best results. Also a new method of protection-deprotection of amines as carbamates has been developed. Smooth deprotection is possible by the palladium-catalyzed reaction of allyl carbamates with formic acid. This method is particulary useful for primary amines, including optically active amino acids. 相似文献
24.
Dehydrroxy-trans-resorcylide () was synthesized by efficient intramolecular alkylation of the protected cyanohydrin. The butadiene telomer obtained by the palladium catalyzed reaction of butadiene with acetic acid was used as a suitable block of the carbocycle. 相似文献
25.
26.
Allen WH Bond IA Budding E Conway MJ Daniel A Fenton KB Fujii H Fujii Z Hayashida N Hibino K Honda M Humble JE Kabe S Kasahara K Kifune T Lythe GD Masaike A Matsubara Y Mitsui K Miura Y Mori M Muraki Y Nagano M Nakamura T Nishizawa M Morris PM Ogio S Saito T Sakata M Sato H Shimizu HM Spencer M Storey JR Tanimori T Teshima M Torii S Wadsworth A Watase Y Woodhams MD Yamamoto Y Yock PC Yuda T 《Physical review D: Particles and fields》1993,48(2):466-478
27.
Angiotensin I‐converting enzyme (ACE) inhibitory peptide was isolated from the hen ovotransferrin hydrolysate using chymotryptic hydrolysis by two steps of reverse‐phase high‐performance liquid chromatography. The amino sequence of this novel peptide was identified as Lys‐Val‐Arg‐Glu‐Gly‐Thr‐Thr‐Tyr that inhibited ACE activity in vitro in a concentration‐dependent manner with an effective concentration (IC50) of 102.8 μM. Also, this inhibition was identified as noncompetitive using the Lineweaver‐Burk plot. Moreover, the antihypertensive action of this novel peptide was investigated by an intravenous injection into spontaneously hypertensive rats (SHR). A dose‐dependent reduction of systolic blood pressure by this peptide was observed after 40 min of treatment and it decreased the blood pressure markedly at the maximal dose (1 nmol/mL/kg). The maximal blood pressure lowering activity of this peptide was calculated as 163% of captopril (10 pmol/mL/kg) that was used as positive control. In conclusion, the obtained data suggests that Lys‐Val‐Arg‐Glu‐Gly‐Thr‐Thr‐Tyr has an ability to inhibit ACE activity and decrease the systolic blood pressure in hypertensive animals. 相似文献
28.
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30.
Oxetanes were reacted with lithium enolates generated from esters or amides in the presence of boron trifluoride etherate to give δ-hydroxyesters or amides in high yield, which were hydrolyzed and converted to δ-lactones. 相似文献