Convenient Synthesis of Two Novel Oxazolidines and Primary Research on their Biological Activities

Two novel N-dichloroacetyl oxazolidines were synthesized with a simple, mild and convenient method in good yields. The compounds were Characterized by IR, 1^H NMR and elemental analysis. The preliminary biological test show that the compounds protected maize against injure by chlorsulfuron to some extent.

Simple,Mild and Convenient Synthesis of Two Novel N-Dichloro-acetyl Oxazolidines and their Biological Activities

Two N-dichloroacetyl oxazolidines were synthesized with a simple, mild and convenient method. All the compounds were characterized by IR, HNMR and elemental analysis. The 1 preliminary biological test showed that the compounds protected maize against injury by some herbicides to some extent.

An Efficient Reaction Process for the Synthesis of Oxazinanes, and Oxazolidines in the Presence of Air

After purging air through the mixture of aldehydes and amino alcohols and microwaved the reaction mixture at 50°C for minutes gave the corresponding oxazinanes, and oxazolidines in excellent yields.

A DNMR study on the ring inversion of oxazolidines

Ring inversion of eight substituted 2-phenyl-4,4-dimethyloxazolidines in o-dichloro- benzene-d_4 was studied by ~H DNMR.Very high inversion barriers((?)G_c(?)=86.7—93.4 kJ·mol^(-1)) were found for these oxazolidine rings.The magnitude of the inversion barrier is dependent on the polarity of the substituent on the phenyl group.A linear correlation is present between the (?)G_c(?) of the inversion and the substituent constant,σ^+,of the substituent.

Synthesis and biological activities of N-dichloroacetyl-2-n-propyl-1-oxa-4-aza-spiro-4, 5-decane

The title compound was synthesized and characterized by IR, ^1HNMR and elemental analysis. The preliminary biological test showed that the compound protected maize against injury by imazethapyr to some extent.

Optically Active Chiral Auxiliary Benzyloxyphenylglycinol for Preparation of Oxazolidine and Its Derivatives

To investigate the recovery of amino alcohols as chiral auxiliaries, optically active p-benzyloxyphenylglycinol and its corresponding oxazolidine of 1-naphthylcarboxaldehyde were prepared. Grignard additions to the oxazolidine followed by electrophilic quench and acidic hydrolysis afforded an aldehyde(compound 8)(later it was reduced to an alcohol, compound 9) in an excellent enantiomeric excess and a good recovery of the chiral amino alcohol. This research provides a model study of chiral amino alcohols in solid phase asymmetric synthesis.

Synthesis, Crystal Structure and Biological Activity of Novel Dichloroacetyl Oxazolidine Herbicide Safeners

A series of novel N-dichloroacetyl oxazolidine herbicide safeners was synthesized and characterized by IR, 1H NMR, 13C NMR, elemental analysis and X-ray diffraction. The preliminary biological test shows that the compounds could protect maize against injury caused by chlorsulfuron to a certain extent.

Synthesis of alkynes and alkynyl iodides bearing a protected amino alcohol moiety as functionalized amino acids precursors

Amino acid precursors in protected amino alcohol form are important synthons that can be used as building-blocks for the hemisynthesis of non-natural amino acids.Serine can be used as a common starting material for the synthesis of such compounds differently protected.Particularly,protected amino alcohols bearing an ethynyl and/or an iodoethynyl group can be used in cross-couplings,in 1,3-dipolar cycloadditions and/or in Nozaki-Hiyama-Kishi type reactions.We thus demonstrated that the efficiently protected amino alcohols derived from serine can be coupled to a sugar derivative by an indium mediated alkynylation reaction.The conditions of this coupling are compatible with such functionalized derivatives and allow envisaging an access to C-glycosylated amino acids.

Functional non-glutaraldehyde treated porcine pericardium for anti-coagulation,anti-calcification,and endothelial proliferation bioprosthetic heart valves

In the last decade,the number of transcatheter heart valve replacement for severe heart valve disease has increased exponentially.Although the bioprosthetic artificial heart valve(BHV)has similar fluid dynamics performance to the original heart valve compared with mechanical heart valve so that there is no need to take long-term anticoagulant drugs to prevent thromboembolism,transcatheter BHV replacement are still at risk for thrombosis during the first few months according to the clinical data.However,the use of antithrombotic drugs can also increase the risk of bleeding.Therefore,it is particularly important to improve the anticoagulant properties for the BHV itself.In this work,a kind of non-glutaraldehyde cross-linked BHV material with excellent antithrombotic ability has been prepared from carboxylated oxazolidine treated porcine pericardium(consisting of collagen,elastin and glycoprotein)with the further graft of the anticoagulant heparin sodium via hydrophilic modified chitosan.Along with the similar mechanical properties and collagen stability comparable to the glutaraldehyde cross-linked porcine pericardium(PP),these functional non-glutaraldehyde cross-linked PPs exhibit better biocompatibility,promoted endothelial proliferation and superior anti-calcification ability.More importantly,excellent anticoagulant activity can be observed in the hematological experiments in vivo and in vitro.In summary,these excellent performances make these functional non-glutaraldehyde cross-linked PPs great potentialities in the BHV applications.