Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
Add more filters










Publication year range
1.
Med Drug Discov ; 5: 100036, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32292908

ABSTRACT

This paper provides an overview of the current global market and manufacturing landscape for hydroxychloroquine (HCQ). The capacity and capabilities of global producers to meet the potential demand for treating patients inflicted with COVID-19 by the novel corona virus SARS-CoV-2, should HCQ's efficacy be established by more definitive clinical trials, is also assessed. Given the large existing manufacturing base and abundance of raw materials for HCQ, the supply challenge can be met with considerable efforts and international cooperation. Preemptive and coordinated emergency efforts among global governments, regulatory agencies, chemical and pharmaceutical industries are imperative for meeting the potential surge in demand.

2.
Org Biomol Chem ; 17(11): 3056-3065, 2019 03 13.
Article in English | MEDLINE | ID: mdl-30834400

ABSTRACT

Our annulation strategy utilized for the synthesis of 2-azaspiro[3.4]octane is explained. Three successful routes for the synthesis were developed. One of the approaches involved annulation of the cyclopentane ring and the remaining two approaches involved annulation of the four membered ring. All three approaches employ readily available starting materials with conventional chemical transformations and minimal chromatographic purifications to afford the title compound. The merits and limitations of the three approaches are also discussed.

3.
Chem Commun (Camb) ; (10): 1232-4, 2008 Mar 14.
Article in English | MEDLINE | ID: mdl-18309427

ABSTRACT

The addition of nitroalkanes to alpha,beta-unsaturated aldehydes under the catalysis of (S)-2-(diphenyl(trimethylsilyloxy)methyl)pyrrolidine and lithium acetate as additive afforded gamma-nitroaldehydes in good yield and up to 97% ee.


Subject(s)
Aldehydes/chemistry , Alkanes/chemistry , Nitrogen Compounds/chemistry , Stereoisomerism
4.
Environ Sci Technol ; 41(10): 3747-51, 2007 May 15.
Article in English | MEDLINE | ID: mdl-17547207

ABSTRACT

Assistance and acceleration of the environment's self-remediation of pollutants represent an important and long-standing goal for environmental chemistry communities. Here, a degradation route using a combination of a nitrite and a ferric salt as the photocatalyst is presented for catalytically removing 17beta-estradiol (E2), estriol (E3), and 17alpha-ethynylestradiol (EE2) in water under mimicked natural environmental conditions, i.e., in the phytotron. After a 1 day reaction, 86.6% of the estrogen E2 was degraded. Extending the incubation time to 30 days, more than 99.9% E2 was removed and a very small quantity of malonic acid observed as the residual organic compound, and estrogenic activity was determined. The results showed that the estrogenic activities of the intermediate products are negligible and that there is no secondary risk associated with increased the estrogenic activity. The degradation system demonstrated that FeCl3/NaN02 is an efficient photocatalyst which is active on natural light irradiation. This work highlights a promising development for in situ treatment of pollutants in natural-environment conditions.


Subject(s)
Estrogens/chemistry , Ferric Compounds/chemistry , Light , Sodium Nitrite/chemistry , Water/chemistry , Catalysis/radiation effects , Chlorides , Estrogens/analysis , Estrogens/isolation & purification , Gas Chromatography-Mass Spectrometry , Solutions
6.
J Org Chem ; 71(17): 6522-9, 2006 Aug 18.
Article in English | MEDLINE | ID: mdl-16901139

ABSTRACT

A series of 2-dialkylphosphino-2'-alkoxy-1,1'-binaphthyl ligands (6a-c and 8a-c) have been prepared conveniently by a lithium-initiated ring-opening reaction of dinaphthofuran, followed by selective phosphorylation. These compounds displayed a remarkable air and moisture stability, both in solid form and in solution. Application of these phosphine ligands in palladium-catalyzed C-N bond forming reactions revealed the crucial roles of the steric bulk of the substituents on the phosphorus atom governing the catalytic activity. Specifically, 2-di-tert-butylphosphino-2'-isopropoxy-1,1'-binaphthyl (8b) proved to be the most effective for the aminations of aryl halides with primary amines, while the less bulky 2-dicyclohexyl-2'-methoxy-1,1'-binaphthyl (6a) was more effective for the aminations with secondary amines. The steric and electronic effects of the ligands were analyzed to account for these observations.


Subject(s)
Carbon/chemistry , Electrons , Nitrogen/chemistry , Nitrosamines/chemistry , Palladium/chemistry , Amination , Amines/chemistry , Catalysis , Halogens/chemistry , Ligands , Molecular Structure
8.
J Org Chem ; 71(2): 826-8, 2006 Jan 20.
Article in English | MEDLINE | ID: mdl-16409004

ABSTRACT

[reaction: see text] Oxidation of alkynes to alpha-dicarbonyl derivatives through a convenient one-pot procedure via a Brønsted acid-promoted "hydration" and a DMSO-based oxidation sequence has been achieved in high yields. The scope and limitations of the reaction have also been investigated.


Subject(s)
Alkynes/chemistry , Ketones/chemistry , Ketones/chemical synthesis , Dimethyl Sulfoxide , Indicators and Reagents , Models, Molecular , Molecular Conformation , Oxidation-Reduction
10.
Invest New Drugs ; 23(3): 213-24, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15868377

ABSTRACT

Cryptophycins-1 and 52 (epoxides) were discovered to have in-vitro and in-vivo antitumor activity in the early 1990s. The chlorohydrins of these, Cryptophycins-8 and 55 (also discovered in the early 1990s) were markedly more active, but could not be formulated as stable solutions. With no method to adequately stabilize the chlorohydrins at the time, Cryptophycin-52 (LY 355073) entered clinical trials, producing only marginal antitumor activity. Since that time, glycinate esters of the hydroxyl group of the chlorohydrins have been synthesized and found to provide stability. Three of the most active were compared herein. Cryptophycin-309 (C-309) is a glycinate ester of the chlorohydrin Cryptophycin-296. The glycinate derivative provided both chemical stability and improved aqueous solubility. After the examination of 81 different Cryptophycin analogs in tumor bearing animals, C-309 has emerged as superior to all others. The following %T/C and Log Kill (LK) values were obtained from a single course of IV treatment (Q2d x 5) against early staged SC transplantable tumors of mouse and human origin: Mam 17/Adr [a pgp (+) MDR tumor]: 0%T/C, 3.2 LK; Mam 16/C/Adr [a pgp (-) MDR tumor]: 0%T/C, 3.3 LK; Mam 16/C: 0%T/C, 3.8 LK; Colon 26: 0%T/C, 2.2 LK; Colon 51: 0%T/C, 2.4 LK; Pancreatic Ductal Adenocarcinoma 02 (Panc 02): 0%T/C, 2.4 LK; Human Colon HCT15 [a pgp (+) MDR tumor]: 0%T/C, 3.3 LK; Human Colon HCT116: 0%T/C, 4.1 LK. One additional analog, Cryptophycin-249 (C-249, the glycinate of Cryptophycin-8), also emerged with efficacy rivaling or superior to C-309. However, there was sufficient material for only a single C-249 trial in which a 4.0 LK was obtained against the multidrug resistant breast adenocarcinoma Mam-16/C/Adr. C-309 and C-249 are being considered as second-generation clinical candidates.


Subject(s)
Antineoplastic Agents/pharmacology , Depsipeptides/pharmacology , Epoxy Compounds/pharmacology , Neoplasms, Experimental/drug therapy , Peptides, Cyclic/pharmacology , Animals , Antineoplastic Agents/chemistry , Depsipeptides/chemistry , Drug Screening Assays, Antitumor , Epoxy Compounds/chemistry , Esters , Humans , Mice , Mice, Inbred BALB C , Mice, Inbred ICR , Mice, SCID , Neoplasm Transplantation , Peptides, Cyclic/chemistry , Structure-Activity Relationship
11.
Org Lett ; 7(10): 1947-50, 2005 May 12.
Article in English | MEDLINE | ID: mdl-15876026

ABSTRACT

The synthesis of the peroxime proliferator activated receptor (PPAR) alpha,gamma-agonist (1) was accomplished with high enantio- and diastereoselectivity by employing an asymmetric hydrogenation strategy, of an alpha-alkoxy cinnamic acid derivative, to set the C-2 chiral center. A diastereospecific S(N)2 displacement under mild basic conditions established the C-10 stereochemistry without any detectable racemization of the two epimerizable chiral centers.


Subject(s)
Cinnamates/chemistry , Combinatorial Chemistry Techniques , PPAR alpha/agonists , PPAR gamma/agonists , Propionates/chemical synthesis , Hydrogenation , Molecular Structure , Propionates/chemistry , Propionates/pharmacology , Stereoisomerism
12.
Bioorg Med Chem Lett ; 15(1): 51-5, 2005 Jan 03.
Article in English | MEDLINE | ID: mdl-15582409

ABSTRACT

Herein we describe a series of potent and selective PPARgamma agonists with moderate PPARalpha affinity and little to no affinity for other nuclear receptors. In vivo studies in a NIDDM animal model (ZDF rat) showed that these compounds are efficacious at low doses in glucose normalization and plasma triglyceride reduction. Compound 1b (LY519818) was selected from our SAR studies to be advanced to clinical evaluation for the treatment of type II diabetes.


Subject(s)
Cinnamates/pharmacology , Diabetes Mellitus, Type 2/metabolism , Peroxisome Proliferator-Activated Receptors/agonists , Animals , Blood Glucose/metabolism , Cinnamates/administration & dosage , Cinnamates/chemistry , Disease Models, Animal , Dose-Response Relationship, Drug , Rats , Rats, Zucker , Structure-Activity Relationship , Triglycerides/blood
13.
Org Biomol Chem ; 1(18): 3227-31, 2003 Sep 21.
Article in English | MEDLINE | ID: mdl-14527156

ABSTRACT

Five 1,3-disubstituted imidazolium salts were synthesized. Their Heck reaction activities were evaluated. A convenient, efficient and high yielding procedure based on these compounds for the arylation of olefins was developed. Heck reactions mediated by these palladium-N-heterocyclic carbene complexes were conducted under air and even in the presence of several common oxidants.


Subject(s)
Chemistry, Organic/methods , Imidazoles/chemistry , Methane/analogs & derivatives , Methane/chemistry , Palladium/chemistry , Catalysis , Hydrocarbons , Ligands , Models, Chemical , Time Factors
14.
Org Biomol Chem ; 1(10): 1643-6, 2003 May 21.
Article in English | MEDLINE | ID: mdl-12926349

ABSTRACT

A highly effective, easy to handle and environmentally benign process for palladium mediated Suzuki cross-coupling was developed. By utilizing a solid support based NHC-palladium catalyst, cross couplings of aryl bromides with phenylboronic acid were achieved in neat water under air. A high ratio of substrate to catalyst was also realized.

SELECTION OF CITATIONS
SEARCH DETAIL
...