We present the case of a 61-year-old man who underwent I-123 metaiodobenzylguanidine (MIBG) scintigraphy based on clinical suspicion of pheochromocytoma. The study was nondiagnostic secondary to diffuse muscle uptake. On review of his medications, the patient was found to be taking mirtazapine, a tetracyclic antidepressant (Remeron). We hypothesize that the MIBG biodistribution was altered by m...

A synthetic strategy for the modeling construction of the highly bridged azatetracyclic ABEF ring system of numerous lycoctonine-type C19-diterpenoid alkaloids bearing a characteristic oxygenated quaternary center at C-7 has been successfully developed. The tetracyclic core was constructed rapidly from a readily prepared 6,7-bicyclic AB ring precursor through a 13-step sequence via an advanced ...

Efficient palladium-catalysed cascade cyclisation to form spiroindoles is developed. Treatment of indoles bearing a propargyl chloride side chain at the 3-position with various external nucleophiles in the presence of a catalytic amount of Pd2(dba)3·CHCl3/dppb and Cs2CO3 in THF gives fused tetracyclic spiroindoles in moderate to good yields.

[reaction: see text] This Letter describes the synthesis of the hemibrevetoxin B tetracyclic ring system in 14 linear transformations from the Danishefsky-Kitahara diene.

Two high-yielding strategies for the synthesis of 4H-anthra[1,2-b]pyran antibiotics have been developed giving access to novel antitumor agent (ED(50) 1.5 microm) and to (S)-espicufolin (3). A key step for the assembly of the tetracyclic 4H-anthra[1,2-b]pyran-4,7,12-trione skeleton is the nucleophilic addition of an aryl lithium species onto an aldehyde which allows the introduction of either a...

Highly strained biarylazacyclooctynone (BARAC) and analogous bioconjugation reagents were shown to undergo novel rearrangement and addition reactions leading to tetracyclic products. This may limit their practical applicability as bioorthogonal reporters for imaging biomolecules within living systems.

Syntheses of the reported structures of kealiinines B and C have been executed. An intermolecular electrophile-induced cyclization of a pendant arene on an ene-guanidine affords the tetracyclic, oxidized naphthimidazole cores.

A simple and straightforward synthetic approach to potential anti-infective thiolactone-isatin hybrids led to the discovery of novel tetracyclic compounds which bear a macrocylic motif containing an unusual bridged amide bond.

During efforts to prepare the known compound , a new tetracyclic compound, called VG1, was prepared in six steps. This compound was found to have good activity as an inhibitor of nonsense-mediated mRNA decay.