Isolation and Chemical Transformations of Vasicinone

Vasicinone and peganine were isolated from Peganum harmala L. Vasicinone 2,4-dinitrophenylhydrazone and vasicinone ketal were prepared.     

Amberlyst-15催化C(sp~3)—H对靛红类化合物的加成反应

以Amberlyst-15为催化剂,甲基吡啶类化合物中的C(sp~3)—H键对靛红类化合物经加成反应合成了24个3-羟基-2-吲哚酮类化合物(3a~3x),其中3u~3x为新化合物,其结构经1H NMR,13C NMR,IR和HR-MS(ESI)表征。催化剂Amberlyst-15循环使用8次,不影响反应收率。     

二丁基锡(IV)磺酸酯催化合成缩醛(酮)

用二丁基氧化锡与苯磺酸、甲磺酸反应制备了两种新的有机锡化合物——二丁基锡(IV)磺酸酯. 以二丁基锡(IV)磺酸酯作催化剂, 合成了一系列缩醛(酮), 并通过正交实验, 优化了有机锡催化缩醛(酮)合成反应的反应条件. 实验表明该催化反应产率高, 反应时间短, 催化剂用量少且能回收再利用.     

Biologically active metabolites of the actinobacterium <Emphasis Type="Italic">Streptomyces</Emphasis> sp. GW 33/1593

A new cyclic dipeptide, 3-a[(4-hydroxybenzyl)methyl]hexahydropyrrolo[1,2-a]pyrazine-1,4-dione (1) together with the known compounds, 2,3-dihydroxybenzoic acid (2), and 6-(3-methylbut-2-enyl)isatin (3) were isolated from the actinobacterium Streptomyces sp. GW 33/1593. Compounds 1 and 2 possessed cytotoxic activity against the sea urchin Strongylocentrotus intermedius embryos. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 652–655, March, 2008.     

DABCO-catalyzed synthesis of 3-substituted-3-hydroxyindolin-2-ones in aqueous media

An efficient and greener protocol for easy access to 3-susbstituted-3-hydroxy-2-oxindoles by the reaction with various substituted isatins and acetophenones is described. This protocol is widely applicable for a variety of isatins and acetophenones using water as a reaction media and 1,4-diazabicyclo[2.2.2]octane (DABCO) as catalyst with shorter reaction time and good to excellent yield of products.     

Synthesis and Antiproliferatory Activities Evaluation of Multi-Substituted Isatin Derivatives

A series of multi-substituted isatin derivatives were synthesized using the powerful Sandmeyer reaction. The structures of these derivatives were confirmed by ¹H-NMR, ¹³C-NMR, and HR-MS. Inhibition of proliferation activities of these derivatives against human leukemia cells (K562), human hepatocellular carcinoma cells (HepG2) and human colon carcinoma cells (HT-29) were evaluated in vitro using the MTT assay. Among the series, compound 4l exhibited strong antiproliferatory activities against K562, HepG2 and HT-29 cells with IC₅₀ values of 1.75, 3.20, and 4.17 μM, respectively. The morphological, growth inhibitory and apoptosic effects of compound 4l in K562 cells, wound healing effect in HepG2 cells, and tube formating effect in matrix gel of HUVEC cells were evaluated consequently. All results indicated that compound 4l could be used as a potential antitumor agent in further investigations.     

β-羰基酸与N-Boc靛红亚胺的脱羧Mannich反应合成3-氨基-3,3'-二取代氧化吲哚衍生物

以5 mol%辛克宁衍生的手性双功能硫脲叔胺为催化剂,β-羰基酸和N-Boc靛红亚胺为原料,经脱羧Mannich反应合成了14个3-氨基-3,3'-二取代氧化吲哚衍生物,收率73%~99%,其结构经1H NMR,13C NMR和HR-MS(ESI)确证。     

Organocatalytic Asymmetric Addition of Naphthols and Electron‐Rich Phenols to Isatin‐Derived Ketimines: Highly Enantioselective Construction of Tetrasubstituted Stereocenters

A quinine‐derived thiourea organocatalyst promoted the highly enantioselective addition of naphthols and activated phenols to ketimines derived from isatins. The reaction afforded chiral 3‐amino‐2‐oxindoles with a quaternary stereocenter in high yields (up to 99 %) with excellent enantioselectivity (up to 99 % ee). To the best of our knowledge, this transformation is the first highly enantioselective addition of naphthols to ketimines.     

SBA-15固载磷钨酸催化剂的制备及催化性能

以SBA-15和氨基功能改性的SBA-15／NH2为载体,采用浸渍法制备了固载磷钨酸催化剂,通过FT—IR光谱,Raman光谱,XRD衍射分析,N2-吸附脱附实验,TEM和NH3-TPD等手段对催化剂进行表征．结果表明,磷钨酸在两种载体上均保持Keggin结构,载体的介孔结构没有明显破坏．在高固载量情况下,磷钨酸在SBA-15载体上发生晶相聚集,介孔孔道发生堵塞使比表面积、孔容和孔径明显减小．在SBA-15／NH2载体上,磷钨酸与载体发生酸碱作用,能够均匀分散于SBA-15／NH2的孔道中,但催化剂酸性有所降低．考察了相同固载量的两种催化剂对苹果酯合成反应的催化活性,结果表明,以SBA-15／NH2为载体的催化剂具有良好的重复使用性能．