Clerodane Diterpenoids from <i>Croton crassifolius</i>

Seven new clerodane diterpenoids (<b>1</b>–<b>7</b>) were isolated from roots of <i>Croton crassifolius</i>, along with six known compounds. The structures were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D NMR, and 2D NMR), and the structures of <b>1</b>, <b>3</b>, <b>4</b>, and <b>7</b> were confirmed by single-crystal X-ray diffraction analyses. Compounds <b>1</b>–<b>13</b> were evaluated for in vitro antiviral activity against herpes simplex virus type 1 using the cytopathic effect reduction assay

Clerodane Diterpenoids from <i>Croton crassifolius</i>

Seven new clerodane diterpenoids (<b>1</b>–<b>7</b>) were isolated from roots of <i>Croton crassifolius</i>, along with six known compounds. The structures were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D NMR, and 2D NMR), and the structures of <b>1</b>, <b>3</b>, <b>4</b>, and <b>7</b> were confirmed by single-crystal X-ray diffraction analyses. Compounds <b>1</b>–<b>13</b> were evaluated for in vitro antiviral activity against herpes simplex virus type 1 using the cytopathic effect reduction assay

Clerodane Diterpenoids from <i>Croton crassifolius</i>

Seven new clerodane diterpenoids (<b>1</b>–<b>7</b>) were isolated from roots of <i>Croton crassifolius</i>, along with six known compounds. The structures were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D NMR, and 2D NMR), and the structures of <b>1</b>, <b>3</b>, <b>4</b>, and <b>7</b> were confirmed by single-crystal X-ray diffraction analyses. Compounds <b>1</b>–<b>13</b> were evaluated for in vitro antiviral activity against herpes simplex virus type 1 using the cytopathic effect reduction assay

Clerodane Diterpenoids from <i>Croton crassifolius</i>

Seven new clerodane diterpenoids (<b>1</b>–<b>7</b>) were isolated from roots of <i>Croton crassifolius</i>, along with six known compounds. The structures were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D NMR, and 2D NMR), and the structures of <b>1</b>, <b>3</b>, <b>4</b>, and <b>7</b> were confirmed by single-crystal X-ray diffraction analyses. Compounds <b>1</b>–<b>13</b> were evaluated for in vitro antiviral activity against herpes simplex virus type 1 using the cytopathic effect reduction assay

Matrine-Type Alkaloids from the Roots of <i>Sophora flavescens</i> and Their Antiviral Activities against the Hepatitis B Virus

Eight new matrine-type alkaloids, flavesines G–J (1–4), alopecurine B (5), 7,11-dehydro-oxymatrine (6), 10-oxy-5,6-dehydromatrine (7), and 10-oxysophoridine (8), along with nine known analogues (9–17) were isolated from the roots of Sophora flavescens. Compounds 1–3 are the first natural matrine-type alkaloids with an open-loop ring D, while compound 4 represents an unprecedented dimerization pattern constructed from matrine and piperidine, and 5 is the first example of a matrine-type alkaloid with cleavage of the C-5–C-6 bond. The new structures were elucidated by means of spectroscopic data analysis (including NMR, MS, IR, and UV), and the absolute configurations were determined using single-crystal X-ray diffraction and ECD data. The isolated alkaloids were evaluated for their antiviral activity against hepatitis B virus, and compounds 1, 4, 5, 10, and 14 exhibited comparable antiviral potencies to matrine

Clerodane Diterpenoids from <i>Croton crassifolius</i>

Seven new clerodane diterpenoids (<b>1</b>–<b>7</b>) were isolated from roots of <i>Croton crassifolius</i>, along with six known compounds. The structures were elucidated by extensive spectroscopic methods (IR, UV, HRESIMS, 1D NMR, and 2D NMR), and the structures of <b>1</b>, <b>3</b>, <b>4</b>, and <b>7</b> were confirmed by single-crystal X-ray diffraction analyses. Compounds <b>1</b>–<b>13</b> were evaluated for in vitro antiviral activity against herpes simplex virus type 1 using the cytopathic effect reduction assay

Dimeric Matrine-Type Alkaloids from the Roots of <i>Sophora flavescens</i> and Their Anti-Hepatitis B Virus Activities

Six unusual matrine-type alkaloid dimers, flavesines A–F (<b>1–6</b>, respectively), together with three proposed biosynthetic intermediates (<b>7–9</b>) were isolated from the roots of <i>Sophora flavescens</i>. Compounds <b>1–5</b> were the first natural matrine-type alkaloid dimers, and compound <b>6</b> represented an unprecedented dimerization pattern constructed by matrine and (−)-cytisine. Their structures were elucidated by NMR, MS, single-crystal X-ray diffraction, and a chemical method. The hypothetical biogenetic pathways of <b>1–6</b> were also proposed. Compounds <b>1–9</b> exhibited inhibitory activities against hepatitis B virus

Three new diterpenoids from <i>Croton laui</i> Merr. et Metc

<p>Three new diterpenoids, including one labdane diterpenoid (<b>1</b>) and two cembrane diterpenoids (<b>2</b>–<b>3</b>), were isolated from the aerial parts of <i>Croton laui</i>, along with four known analogues (<b>4</b>–<b>7</b>). Their structures were elucidated by spectroscopic analysis and comparison with literature data. All compounds were evaluated for their cytotoxicity against two tumour cell lines.</p

Four Matrine-Based Alkaloids with Antiviral Activities against HBV from the Seeds of Sophora alopecuroides

Four novel matrine-based alkaloids (<b>1</b>–<b>4</b>) were isolated from the seeds of Sophora alopecuroides. Compounds <b>1</b> and <b>2</b> possess unprecedented 6/6/6/4 and 6/5/6/6 ring systems, respectively, while <b>3</b> and <b>4</b> are a pair of stereoisomeric matrine–acetophenone alkaloids with an unusual skeleton. Their structures were elucidated by means of spectroscopic methods and single-crystal X-ray diffraction. Hypothetical biogenetic pathways for <b>1</b>–<b>4</b> are proposed, and their antiviral activities are also discussed