- Method for preparing mercaptocarboxylic acid or derivatives thereof by aminolysis of thioureidocarboxylic acid or derivatives thereof
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The invention relates to a method for preparing mercaptocarboxylic acid or derivatives thereof by aminolysis of thioureidocarboxylic acid or derivatives thereof. The method mainly comprises the following steps: 1, dissolving thioureidocarboxylic acid or a derivative thereof in ammonia water or a mixed solution of ammonia water and a cosolvent, heating the system to 40-150 DEG C, and reacting for long time until reaction of the thioureido salt is finished; 2, cooling the reaction system, neutralizing the reaction system by using acid, removing the solvent by using a solvent extraction system, and separating to obtain the mercaptocarboxylic acid or the derivative thereof; and 3, concentrating and filtering the residual water phase or organic phase, recycling the distilled water phase or organic phase, and taking the solid ammonium salt mixture as a nitrogen fertilizer. According to the method, the defects that pollutants are complex and difficult to treat, and the environment is pollutedin the prior art that metal ions such as NaOH are adopted for alkaline hydrolysis of thioureidocarboxylic acid and derivatives thereof to prepare mercaptocarboxylic acid and derivatives thereof are overcome. The method has the advantages of simple process, low cost, no environmental pollution and the like, and can basically realize zero emission of three wastes.
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Paragraph 0011
(2020/06/09)
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- Redox responsive paclitaxel dimer for programmed drug release and selectively killing cancer cells
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Redox stimulus responsive drug delivery systems have been widely investigated and proved to be promising prospects for efficient cancer therapy due to the abnormal high level of reactive oxygen species and glutathione in tumor microenvironment. Herein, three paclitaxel dimers (named as PTX2-R, R = S, Se and Te) bridged with alkyl sulfide, selenide or telluride are synthesized. These dimers can self-assemble into stable uniform nanoparticles (named as PTX2-R NPs, R = S, Se and Te) with impressively high drug loading. As expected, sulfur/selenium/tellurium bonds exhibit different redox responsiveness, thereby affecting the drug release and cytotoxicity. Of note, tellurium bridged paclitaxel dimer shows ultra-sensitivity to hydrogen peroxide, which rapidly cleaves into two paclitaxel under the subsequent dithiothreitol stimulation. Our findings provide deep insight into the redox sensitivity of chalcogenide elements and offer the rational design strategies to biologically redox condition for programmed drug release.
- Hu, Xiuli,Pei, Qing,Wang, Jian,Wang, Zhanfeng,Xia, Rui,Xie, Zhigang
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p. 785 - 793
(2020/07/30)
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- CONTROLLED-RELEASE CNP AGONISTS WITH LOW INITIAL NPR-B ACTIVITY
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The present invention relates to a controlled-release CNP agonist from which CNP agonist is released with a release half-life of at least 6 hours under physiological conditions and which controlled-release CNP agonist has an EC50 that is at lea
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Page/Page column 222
(2017/08/01)
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- CNP PRODRUGS WITH CARRIER ATTACHMENT AT THE RING MOIETY
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The present invention relates to CNP prodrugs in which the carrier is covalently and reversibly attached to the ring moiety of a CNP moiety, to pharmaceutical compositions comprising such CNP prodrugs, to their uses and to methods of treating diseases that can be treated with the CNP prodrugs of the present invention.
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Page/Page column 214; 215
(2017/08/01)
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- CONTROLLED-RELEASE CNP AGONISTS WITH INCREASED NEP STABILITY
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The present invention relates to controlled-release CNP agonists having an at least 5-fold longer degradation half-life in an in vitro NEP degradation assay than the corresponding released CNP agonist, to pharmaceutical compositions comprising said contro
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Page/Page column 218-219
(2017/08/01)
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- CONTROLLED-RELEASE CNP AGONISTS WITH REDUCED SIDE-EFFECTS
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The present invention relates a pharmaceutical composition comprising a controlled-release CNP agonist which reduces CNP agonist-associated side-effects, the use of such controlled-release CNP agonist and to methods of treatment.
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Page/Page column 217-218
(2017/08/01)
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- Poly(thioester) by Organocatalytic Ring-Opening Polymerization
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Organocatalysts typically used for the ring-opening polymerization (ROP) of cyclic ester monomers are applied to a thiolactone, ε-thiocaprolactone (tCL). In the absence of an H-bond donor, a nucleophilic polymerization mechanism is proposed. Despite the decreased ability of thioesters and thiols (versus esters and alcohols) to H-bond, H-bonding organocatalysts - a thiourea in combination with an H-bond accepting base - are also effective for the ROP of tCL. The increased nucleophilicity of thiols (versus alcohols) is implicated in the increased Mw/Mn of the poly(thiocaprolactone) versus poly(caprolactone), but deleterious transesterification is suppressed in the presence of a thiourea. The thioester monomer, tCL, is shown to be thermodynamically similar to ε-caprolactam but kinetically similar to ε-caprolactone. (Chemical Equation Presented).
- Bannin, Timothy J.,Kiesewetter, Matthew K.
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p. 5481 - 5486
(2015/09/02)
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- Process for the modification of surface
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The present invention relates to a process for the modification of a material surface comprising the steps of (a1) photochemically fixing one or more different compounds of formula onto the material surface, or (a2) photochemically f
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Page column 7-8
(2010/02/08)
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- Immobilisation on polystyrene of diazirine derivatives of mono- and disaccharides: Biological activities of modified surfaces
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The potential of surface glycoengineering for biomaterials and biosensors originates from the importance of carbohydrate protein interactions in biological systems. The strategy employed here utilises carbene generated by illumination of diazirine to achieve covalent bonding of carbohydrates. Here, we describe the synthesis of an aryl diazirine containing a disaccharide (lac-tose). Surface analysis techniques [X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectroscopy (ToF-SIMS)] demonstrate its successful surface immobilisation on polystyrene (PS). Results are compared to those previously obtained with an aryl diazirine containing a monosaccharide (galactose). The biological activity of galactose- or lactose-modified PS samples is studied using rat hepatocytes, Allo A lectin and solid-phase semi-synthesis with α-2,6-sialyltransferase. Allo A shows some binding to galactose-modified PS but none to lactose-modified surfaces. Similar results are obtained with rat hepatocytes. In contrast, sialylation of lactose-modified PS is achieved but not with galactose-modified surfaces. The different responses indicate that the biological activity depends not only on the carbohydrate per se but also on the structure and length of the spacer. Copyright
- Chevolot,Martins,Milosevic,Leonard,Zeng,Malissard,Berger,Maier,Mathieu,Crout,Sigrist
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p. 2943 - 2953
(2007/10/03)
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- S-4-Methoxytrityl mercapto acids: Synthesis and application
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4-Methoxytrityl (Mmt)-mercapto acids were obtained either by the reaction of mercapto acids with Mmt-chloride or by the reaction of halo acids with Mmt-thiol. The derivatives obtained were used in the solid-phase synthesis of small libraries of mercaptoacylamino acids and mercaptoacyl peptides. The removal of the Mmt-group was performed by treatment with trifluoroacetic acid (TFA) in dichloromethane (DCM) using triethylsilane (TES) as scavenger.
- Mourtas, Spyros,Gatos, Dimitrios,Kalaitzi, Vagiani,Katakalou, Christina,Barlos, Kleomenis
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p. 6965 - 6967
(2007/10/03)
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- PROSTANOIDS. HYBRID 7-THIA-16-ARYLOXY-9,11-DIDEOXY-10-KETOPROSTANOIDS
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The 7-thia-16-aryloxy-9,11-dideoxy-10-keto analogs of prostaglandin E1 were obtained by the conjugate 1,4-addition of 6-mercaptohexanoic and 5-mercaptomethylfuran-2-carboxylic esters to 4-(3-hydroxy-4-phenoxy-1E-butenyl)-2-cyclopenten-1-one.It was established that the addition takes place with the preferential formation of the isomers with the trans arrangement of the side chains.
- Miftakhov, M. S.,Danilova, N. A.,Vel'der, Ya. L.,Sultanmuratova, V. R.,Berg, A. A.,Tolstikov, G. A.
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p. 1681 - 1685
(2007/10/02)
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- Organotin-containing composition for the stabilization of polymers of vinyl chloride
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An organotin-containing composition for the stabilization of polymers or copolymers of vinyl chloride in which there is incorporated a stabilizing amount of an organotin compound containing at least two tin atoms and which is a mercapto, hydroxy or alkoxy substituted ester of a mercapto acid substituted organotin mercapto acid diester.
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- Azole derivatives
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Azole derivatives of the formula SPC1 Wherein R1 is free or esterified carboxyl or other functionally modified carboxyl group, R2 and R3 each are aryl; A is Cn H2n in which n is an integer from 1 to 10, inclusive; and Z is O or S; and the physiologically acceptable salts thereof, possess, with good compatibility, excellent antiphlogistic activity and, in particular, influence favorably the chronic progressive diseases of the joints, e.g., arthritis. They can be prepared from compounds of the formula SPC2 Wherein X1 is a group convertible into the group --S--A--R1, and R2 and R3 have the values given above.
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