Polymer-Supported BINOL Ligand for the Titanium-Catalyzed Diethylzinc Addition to Aldehydes: A Remarkable Positive Influence of the Support on the Enantioselectivity of the Catalyst

A new polymer-supported BINOL (1,1‘-Bi-2-naphthol) was synthesized by coupling of aminomethyl polystyrene resin and (S)-2,2‘-dihydroxy-1,1‘-binaphthyl-3,3‘-dicarboxylic acid. This new ligand was found to be more enantioselective for the asymmetric addition of diethylzinc to aldehydes than its “free” analog [Ti(BINOL)iPrO2]. A range of 57−99% ee's as well as 78−97% yields was obtained, and the electronic properties of the enantioselectivity were also observed

Antiviral Matrine-Type Alkaloids from the Rhizomes of <i>Sophora tonkinensis</i>

Three new matrine-type alkaloids, (+)-5α-hydroxyoxy­sophocarpine (<b>1</b>), (−)-12β-hydroxyoxy­sophocarpine (<b>2</b>), and (+)-5α-hydroxylemannine (<b>3</b>), along with 14 known analogues, (−)-sophocarpine (<b>4</b>), (−)-5α-hydroxy­sophocarpine (<b>5</b>), (−)-9α-hydroxy­sophocarpine (<b>6</b>), (+)-12α-hydroxy­sophocarpine (<b>7</b>), (−)-12β-hydroxy­sophocarpine (<b>8</b>), (+)-oxysophocarpine (<b>9</b>), (+)-matrine (<b>10</b>), (+)-sophoranol (<b>11</b>), (+)-9α-hydroxy­matrine (<b>12</b>), (−)-14β-hydroxy­matrine (<b>13</b>), (+)-oxymatrine (<b>14</b>), (+)-5α-hydroxyoxymatrine (<b>15</b>), (−)-14β-hydroxyoxy­matrine (<b>16</b>), and (+)-sophoramine (<b>17</b>), were isolated from the rhizomes of <i>Sophora tonkinensis</i>. Their structures were elucidated via spectrometric data analyses, and the absolute configurations were established by single-crystal X-ray diffraction and ECD data. Alkaloids <b>2</b>, <b>6</b>, <b>11</b>, and <b>13</b> exhibited antiviral activity against the Coxsackie virus B3 (CVB3), with IC₅₀ values of 26.62–252.18 μM, and alkaloids <b>7</b>, <b>8</b>, and <b>17</b> inhibited influenza virus A/Hanfang/359/95 (H3N2) replication with IC₅₀ values of 63.07–242.46 μM

Ce(OTf)₃‑Catalyzed [3 + 2] Cycloaddition of Azides with Nitroolefins: Regioselective Synthesis of 1,5-Disubstituted 1,2,3-Triazoles

The first example of rare earth metal-catalyzed [3 + 2] cycloaddition of organic azides with nitroolefins and subsequent elimination reaction is described. In the presence of a catalytic amount of Ce­(OTf)3, both benzyl and phenyl azides react with a broad range of aryl nitroolefins containing a range of functionalities selectively producing 1,5-disubstituted 1,2,3-triazoles in good to excellent yields

Palladium-Catalyzed Synthesis of 5‑Iminopyrrolones through Isocyanide Double Insertion Reaction with Terminal Alkynes and Water

With the combination of Pd­(dppf)­Cl₂ and Cu­(OAc)₂, a variety of 5-iminopyrrolones were synthesized in moderate to good yields from terminal alkynes, isocyanide, and water via isocyanide double insertion and cycloaddition reaction. A plausible reaction mechanism for this process is depicted. Furthermore, selected compounds <b>3c</b>, <b>3e</b>, and <b>3h</b> exhibited good activities against HepG2 (human liver cancer), NCI-H460 (human lung cancer), and SK-OV-3 (human ovarian cancer) cell lines with IC₅₀ values in the range of 10.63–22.63 μmol L^–1

Glycosides with galloyl groups from <i>Balakata baccata</i> and their antineuroinflammatory activities

Seven new glycosides (1 − 7) with galloyl groups and two known kaempferol glycosides (8 and 9) were obtained from the overground parts of Balakata baccata. The structures of the new compounds were determined by comprehensive spectroscopic analyses. The rarely seen allene moiety in compounds 6 and 7 were described by detailed analysis of 1D and 2D NMR data. The antineuroinflammatory effect of all the isolates was assessed through inhibiting nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglial cells. Compounds 1, 2, 6, and 7 showed potent inhibitory activities with IC50 values of 25.7, 17.2, 15.5 and 24.4 μM, respectively, compared with the positive control minocycline (IC50 = 16.1 μM).</p

Atom-Economical Chemoselective Synthesis of 1,4-Enynes from Terminal Alkenes and Propargylic Alcohols Catalyzed by Cu(OTf)₂

A novel and efficient Cu­(OTf)₂-catalyzed sp³–sp² C–C bond formation reaction through the direct coupling of propargylic alcohols with terminal alkenes has been realized under mild conditions. The reaction is tolerant to air and is atom-economical, in accordance with the concept of modern green chemistry. The present protocol provides an attractive approach to a diverse range of 1,4-enynes in high to excellent yields

Antiviral Matrine-Type Alkaloids from the Rhizomes of <i>Sophora tonkinensis</i>

Three new matrine-type alkaloids, (+)-5α-hydroxyoxy­sophocarpine (<b>1</b>), (−)-12β-hydroxyoxy­sophocarpine (<b>2</b>), and (+)-5α-hydroxylemannine (<b>3</b>), along with 14 known analogues, (−)-sophocarpine (<b>4</b>), (−)-5α-hydroxy­sophocarpine (<b>5</b>), (−)-9α-hydroxy­sophocarpine (<b>6</b>), (+)-12α-hydroxy­sophocarpine (<b>7</b>), (−)-12β-hydroxy­sophocarpine (<b>8</b>), (+)-oxysophocarpine (<b>9</b>), (+)-matrine (<b>10</b>), (+)-sophoranol (<b>11</b>), (+)-9α-hydroxy­matrine (<b>12</b>), (−)-14β-hydroxy­matrine (<b>13</b>), (+)-oxymatrine (<b>14</b>), (+)-5α-hydroxyoxymatrine (<b>15</b>), (−)-14β-hydroxyoxy­matrine (<b>16</b>), and (+)-sophoramine (<b>17</b>), were isolated from the rhizomes of <i>Sophora tonkinensis</i>. Their structures were elucidated via spectrometric data analyses, and the absolute configurations were established by single-crystal X-ray diffraction and ECD data. Alkaloids <b>2</b>, <b>6</b>, <b>11</b>, and <b>13</b> exhibited antiviral activity against the Coxsackie virus B3 (CVB3), with IC₅₀ values of 26.62–252.18 μM, and alkaloids <b>7</b>, <b>8</b>, and <b>17</b> inhibited influenza virus A/Hanfang/359/95 (H3N2) replication with IC₅₀ values of 63.07–242.46 μM

Ce(OTf)₃‑Catalyzed [3 + 2] Cycloaddition of Azides with Nitroolefins: Regioselective Synthesis of 1,5-Disubstituted 1,2,3-Triazoles

The first example of rare earth metal-catalyzed [3 + 2] cycloaddition of organic azides with nitroolefins and subsequent elimination reaction is described. In the presence of a catalytic amount of Ce­(OTf)₃, both benzyl and phenyl azides react with a broad range of aryl nitroolefins containing a range of functionalities selectively producing 1,5-disubstituted 1,2,3-triazoles in good to excellent yields

Antiviral Matrine-Type Alkaloids from the Rhizomes of <i>Sophora tonkinensis</i>

Three new matrine-type alkaloids, (+)-5α-hydroxyoxy­sophocarpine (<b>1</b>), (−)-12β-hydroxyoxy­sophocarpine (<b>2</b>), and (+)-5α-hydroxylemannine (<b>3</b>), along with 14 known analogues, (−)-sophocarpine (<b>4</b>), (−)-5α-hydroxy­sophocarpine (<b>5</b>), (−)-9α-hydroxy­sophocarpine (<b>6</b>), (+)-12α-hydroxy­sophocarpine (<b>7</b>), (−)-12β-hydroxy­sophocarpine (<b>8</b>), (+)-oxysophocarpine (<b>9</b>), (+)-matrine (<b>10</b>), (+)-sophoranol (<b>11</b>), (+)-9α-hydroxy­matrine (<b>12</b>), (−)-14β-hydroxy­matrine (<b>13</b>), (+)-oxymatrine (<b>14</b>), (+)-5α-hydroxyoxymatrine (<b>15</b>), (−)-14β-hydroxyoxy­matrine (<b>16</b>), and (+)-sophoramine (<b>17</b>), were isolated from the rhizomes of <i>Sophora tonkinensis</i>. Their structures were elucidated via spectrometric data analyses, and the absolute configurations were established by single-crystal X-ray diffraction and ECD data. Alkaloids <b>2</b>, <b>6</b>, <b>11</b>, and <b>13</b> exhibited antiviral activity against the Coxsackie virus B3 (CVB3), with IC₅₀ values of 26.62–252.18 μM, and alkaloids <b>7</b>, <b>8</b>, and <b>17</b> inhibited influenza virus A/Hanfang/359/95 (H3N2) replication with IC₅₀ values of 63.07–242.46 μM

Inhibition potential of phenolic constituents from the aerial parts of <i>Tetrastigma hemsleyanum</i> against soluble epoxide hydrolase and nitric oxide synthase

The aerial parts of Tetrastigma hemsleyanum (APTH) have been used as a functional tea in China. The purpose of the current study was to identify the bioactive constituents with inhibitory activity against soluble epoxide hydrolase (sEH) and inducible nitric oxide synthase (iNOS), which are jointly considered potential therapeutic targets for vascular system diseases. In the present study, 39 compounds (1–39) were isolated from the APTH. Among them, compounds 8, 10, 12, 16, 17, 19, and 32 displayed potential activities, with IC50 values ranging from 4.5 to 9.5 µM, respectively, and all in non-competitive inhibition mode. Compounds 5, 10, 12, 19, and 32 displayed potent iNOS inhibitory effects, with IC50 values ranging from 15.6 to 47.3 µM. The results obtained in this work contribute to a better understanding of the pharmacological activities of T. hemsleyanum and its potential application as a functional food.</p