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2.
J Org Chem ; 88(13): 9293-9305, 2023 Jul 07.
Article in English | MEDLINE | ID: mdl-37284734

ABSTRACT

A visible-light-induced three-component reaction of 2-aryl indoles/benzimidazoles, Hantzsch esters, and sodium pyrosulfite through a radical cascade cyclization process with the insertion of sulfur dioxide is described. It provides a novel and powerful way for the synthesis of alkylsulfonated isoquinolinones. Hantzsch esters and Na2S2O5 are employed as alkyl radical precursors and SO2 surrogate, respectively. This transformation exhibits good functional group tolerance and substrate applicability under mild conditions.


Subject(s)
Benzimidazoles , Sulfur Dioxide , Cyclization , Esters , Indoles
3.
J Org Chem ; 88(13): 8563-8575, 2023 Jul 07.
Article in English | MEDLINE | ID: mdl-37339016

ABSTRACT

An efficient strategy for visible-light-promoted decarboxylative alkylation of vinylcyclopropanes with alkyl N-(acyloxy)phthalimide esters through the dual C-C bond and single N-O bond cleavage, employing triphenylphosphine and lithium iodide as the photoredox system to synthesize 2-alkylated 3,4-dihydronaphthalenes, has been established. This alkylation/cyclization involves a radical process and undergoes a sequence of N-(acyloxy)phthalimide ester single-electron reduction, N-O bond cleavage, decarboxylative, alkyl radical addition, C-C bond cleavage, and intramolecular cyclization. Moreover, using the photocatalyst Na2-Eosin Y instead of triphenylphosphine and lithium iodide, the vinyl transfer products are acquired when vinylcyclobutanes or vinylcyclopentanes are utilized as alkyl radical receptors.


Subject(s)
Iodides , Lithium , Cyclization , Alkylation , Esters , Phthalimides
4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-970623

ABSTRACT

Since Curcumae Radix decoction pieces have multiple sources, it is difficult to distinguish depending on traditional cha-racters, and the mixed use of multi-source Curcumae Radix will affect its clinical efficacy. Heracles Neo ultra-fast gas phase electronic nose was used in this study to quickly identify and analyze the odor components of 40 batches of Curcumae Radix samples from Sichuan, Zhejiang, and Guangxi. Based on the odor fingerprints established for Curcumae Radix decoction pieces of multiple sources, the odor components was identified and analyzed, and the chromatographic peaks were processed and analyzed to establish a rapid identification method. Principal component analysis(PCA), discriminant factor analysis(DFA), and soft independent modeling cluster analysis(SIMCA) were constructed for verification. At the same time, one-way analysis of variance(ANOVA) combined with variable importance in projection(VIP) was employed to screen out the odor components with P<0.05 and VIP>1, and 13 odor components such as β-caryophyllene and limonene were hypothesized as the odor differential markers of Curcumae Radix decoction pieces of diffe-rent sources. The results showed that Heracles Neo ultra-fast gas phase electronic nose can well analyze the odor characteristics and rapidly and accurately discriminate Curcumae Radix decoction pieces of different sources. It can be applied to the quality control(e.g., online detection) in the production of Curcumae Radix decoction pieces. This study provides a new method and idea for the rapid identification and quality control of Curcumae Radix decoction pieces.


Subject(s)
Drugs, Chinese Herbal/analysis , Electronic Nose , China , Plant Roots/chemistry , Limonene/analysis , Chromatography, High Pressure Liquid
5.
Org Biomol Chem ; 20(48): 9659-9671, 2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36416184

ABSTRACT

A new protocol is herein described for the direct generation of alkylated indolo/benzoimidazo[2,1-a]isoquinolin-6(5H)-one derivatives by using Hantzsch esters as alkylation radical precursors using a photoredox/K2S2O8 system. This oxidative alkylation of active alkenes involves a radical cascade cyclization process and a sequence of Hantzsch ester single electron oxidation, C-C bond cleavage, alkylation, arylation and oxidative deprotonation.

6.
J Org Chem ; 87(9): 5643-5659, 2022 05 06.
Article in English | MEDLINE | ID: mdl-35416658

ABSTRACT

A method for the preparation of 3-alkylated spiro[4.5]trienones via alkylation/ipso-cyclization of activated alkynes with 4-alkyl-DHPs under transition-metal-free conditions is proposed. This alkylation successively undergoes the generation of alkyl radicals, addition of alkyl radicals to the alkynes, and intramolecular ipso-cyclization. The mechanism studies suggest that the alkylation/ipso-cyclization involves a radical process. This ipso-cyclization procedure shows a series of advantages, such as accessibility, mild conditions, high efficiency, greater safety, and an environmentally friendly method.


Subject(s)
Alkynes , Spiro Compounds , Alkylation , Cyclization
7.
Org Biomol Chem ; 20(9): 1958-1968, 2022 03 02.
Article in English | MEDLINE | ID: mdl-35174824

ABSTRACT

The transition-metal-free alkylation/cyclization of activated alkenes using Hantzsch ester derivatives as effective alkyl reagents is described. A wide variety of valuable oxindoles was constructed in a single step with excellent selectivity. The reaction occurs through the formation of alkyl radical species followed by the tandem addition/annulation of olefins under oxidative conditions. This protocol is expected to offer inspiration for developing novel and efficient applications of Hantzsch esters in organic synthesis.

8.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-927908

ABSTRACT

Derived from Curcuma plants, Curcumae Longae Rhizoma, Curcumae Rhizoma, Wenyujin Rhizoma Concisum, and Curcumae Radix are common blood-activating and stasis-resolving medicinals in clinical practice, which are mainly used to treat amenorrhea, dysmenorrhea, chest impediment and heart pain, and rheumatic arthralgia caused by blood stasis block. According to modern research, the typical components in medicinals derived from Curcuma plants, like curcumin, demethoxycurcumin, bisdemethoxycurcumin, curdione, germacrone, curcumol, and β-elemene, have the activities of hemorheology improvement, anti-platelet aggregation, anti-thrombosis, anti-inflammation, anti-tumor, and anti-fibrosis, thereby activating blood and resolving stasis. However, due to the difference in origin, medicinal part, processing, and other aspects, the efficacy and clinical application are different. The efficacy-related substances behind the difference have not yet been systematically studied. Thus, focusing on the efficacy-related substances, this study reviewed the background, efficacy and clinical application, efficacy-related substances, and "prediction-identification-verification" research method of blood-activating and stasis-resolving medicinals derived from Curcuma plants, which is expected to lay a theoretical basis for the future research on the "similarities and differences" of such medicinals based on integrated evidence chain and to guide the scientific and rational application of them in clinical practice.


Subject(s)
Curcuma , Curcumin , Drugs, Chinese Herbal , Plant Roots , Platelet Aggregation , Rhizome
9.
J Org Chem ; 86(19): 13720-13733, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34523335

ABSTRACT

A convenient and efficient visible-light-induced tandem acylation/cyclization of N-propargylindoles with aryl- or alkyl-substituted acyl oxime esters for the synthesis of 2-acyl-substituted 9H-pyrrolo[1,2-a]indoles under transition-metal-free conditions, which proceeds via nitrogen-centered radical-mediated cleavage of the C-C σ-bond in acyl oxime esters, is established. The aryl or alkyl acyl radicals, which come from acyl oxime esters, attack the C-C triple bonds in N-propargylindoles and then go through intramolecular cyclization/isomerization.

10.
Endocr Connect ; 10(8): 861-872, 2021 Jul 28.
Article in English | MEDLINE | ID: mdl-34319253

ABSTRACT

Plasma free fatty acids (FFAs) are elevated in obesity and can induce insulin resistance via endoplasmic reticulum (ER) stress. However, it is unknown whether hepatic insulin resistance caused by the elevation of plasma FFAs is alleviated by chemical chaperones. Rats received one of the following i.v. treatments for 48 h: saline, intralipid plus heparin (IH), IH plus the chemical chaperone 4-phenylbutyric acid (PBA), or PBA alone and a hyperinsulinemic-euglycemic clamp was performed during the last 2 h. PBA co-infusion normalized IH-induced peripheral insulin resistance, similar to our previous findings with an antioxidant and an IκBα kinase ß (IKKß) inhibitor. Different from our previous results with the antioxidant and IKKß inhibitor, PBA also improved IH-induced hepatic insulin resistance in parallel with activation of Akt. Unexpectedly, IH did not induce markers of ER stress in the liver, but PBA prevented IH-induced elevation of phosphorylated eukaryotic initiation factor-2α protein in adipose tissue. PBA tended to decrease circulating fetuin-A and significantly increased circulating fibroblast growth factor 21 (FGF21) without affecting markers of activation of hepatic protein kinase C-δ or p38 mitogen-activated protein kinase that we have previously involved in hepatic insulin resistance in this model. In conclusion: (i) PBA prevented hepatic insulin resistance caused by prolonged plasma FFA elevation without affecting hepatic ER stress markers; (ii) the PBA effect is likely due to increased FGF21 and/or decreased fetuin-A, which directly signal to upregulate Akt activation.

11.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-846094

ABSTRACT

The nine times steaming and nine times shining processing method of Polygonatum cyrtonema was originated in ancient China and developed in modern times. The historical evolution of its processing technology includes raw-used, single-steamed, re-steamed, nine times steaming and nine times shining. It can eliminate toxicity, enhance curative effect, change meridians, facilitate storage and eliminate bacteria and so on. After nine times steaming and nine times shining, the chemical composition and drug efficacy of P. cyrtonema changed significantly, and it is widely used in medicine, health care products, common food, cosmetics and other fields. The historical evolution, processing mechanism, composition change, and clinical application of P. cyrtonema are reviewed in this paper, which provide a scientific basis for optimizing the nine times steaming and nine times shining technology of P. cyrtonema, lay the foundation for establishing the quality control standard control system, and provide a reference for the study of observing the ancient processing.

12.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-851708

ABSTRACT

Polygonatum cyrtonema, which is growing in Jiuhua Mountain, is genuine medicinal materials. The main processing methods of it are cutting, single-steamed, re-steamed, nine times steamed and nine times shined, wine-steamed, wine-stewed, copying and so on. Its effective components are polysaccharides and steroidal saponins, and they also have pharmacological activities such as anti-oxidation, regulating immunity, lowering blood sugar, antitumor, antibiosis, and antiviral. The development history and modern research progress of processing technology of P. cyrtonema in Jiuhua Mountain were summarized, which provides reference and basis for its processing research and lays the foundation for its standard operation rules of GMP processing.

13.
J Biol Chem ; 288(48): 34627-37, 2013 Nov 29.
Article in English | MEDLINE | ID: mdl-24142699

ABSTRACT

Glycogen synthesis is a major component of the insulin response, and defective glycogen synthesis is a major portion of insulin resistance. Insulin regulates glycogen synthase (GS) through incompletely defined pathways that activate the enzyme through dephosphorylation and, more potently, allosteric activation. We identify Epm2aip1 as a GS-associated protein. We show that the absence of Epm2aip1 in mice impairs allosteric activation of GS by glucose 6-phosphate, decreases hepatic glycogen synthesis, increases liver fat, causes hepatic insulin resistance, and protects against age-related obesity. Our work identifies a novel GS-associated GS activity-modulating component of insulin resistance.


Subject(s)
Dual-Specificity Phosphatases/genetics , Glycogen Synthase/metabolism , Glycogen/biosynthesis , Insulin Resistance/genetics , Obesity/pathology , Aging/genetics , Animals , Dual-Specificity Phosphatases/metabolism , Glucose-6-Phosphate/metabolism , Glycogen/genetics , Glycogen Synthase/genetics , Humans , Insulin/genetics , Insulin/metabolism , Liver/enzymology , Liver/metabolism , Liver/pathology , Mice , Obesity/etiology , Obesity/genetics , Phosphorylation , Protein Tyrosine Phosphatases, Non-Receptor
14.
J Endocrinol ; 217(1): 31-43, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23328071

ABSTRACT

We have shown in rats that sodium salicylate (SS), which inhibits IkBa kinase B (IKKB), prevents hepatic and peripheral insulin resistance caused by short-term (7  h) i.v. administration of Intralipid and heparin (IH). We wished to further determine whether this beneficial effect of SS persisted after prolonged (48  h) IH infusion, which better mimics the chronic free fatty acid (FFA) elevation of obesity. Hence, we performed hyperinsulinemic euglycemic clamps with tritiated glucose methodology to determine hepatic and peripheral insulin sensitivity in rats infused with saline, IH, IH and SS, or SS alone. SS prevented peripheral insulin resistance (P<0.05) caused by prolonged plasma FFA elevation; however, it did not prevent hepatic insulin resistance. In skeletal muscle, protein levels of phospho-IkBa were augmented by prolonged IH administration and this was prevented by SS, suggesting that IH activates while SS prevents the activation of IKKB. Markers of IKKB activation, namely protein levels of phospho-IkBa and IkBa, indicated that IKKB is not activated in the liver after prolonged FFA elevation. Phosphorylation of serine 307 at insulin receptor substrate (IRS)-1, which is a marker of proximal insulin resistance, was not altered by IH administration in the liver, suggesting that this is not a site of hepatic insulin resistance in the prolonged lipid infusion model. Our results suggest that the role of IKKB in fat-induced insulin resistance is time and tissue dependent and that hepatic insulin resistance induced by prolonged lipid elevation is not due to an IRS-1 serine 307 kinase.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Fatty Acids, Nonesterified/blood , I-kappa B Proteins/antagonists & inhibitors , Insulin Resistance , Liver/drug effects , Obesity/drug therapy , Sodium Salicylate/therapeutic use , Animals , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Disease Models, Animal , Emulsions , Female , Heparin , I-kappa B Proteins/metabolism , Infusions, Intravenous , Kinetics , Liver/metabolism , Muscle, Skeletal/drug effects , Muscle, Skeletal/immunology , Muscle, Skeletal/metabolism , NF-KappaB Inhibitor alpha , Obesity/blood , Obesity/immunology , Obesity/metabolism , Phospholipids , Phosphorylation/drug effects , Protein Processing, Post-Translational/drug effects , Random Allocation , Rats , Rats, Wistar , Sodium Salicylate/administration & dosage , Soybean Oil
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