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Nine new and five known corynanthe alkaloids are isolated as exemplified by the structures shown in the scheme.

Eight new grayanane-type diterpenoids, pieristoxin L-S (1–8), and seven known diterpenoids, grayanoside D (9), rhodomolin I (10), pieristoxin H (11), grayanotoxin II (12), pierisformoside B (13), grayanoside C (14) and bis-deacetylkalmitoxin-VI (15), were isolated from the twigs of Pieris formosa. The structures of these compounds were elucidated using extensive spectroscopic analyses, including electronic circular dichroism (ECD). Pieristoxin L (1) is the first example of a 1,7-epoxy-grayanane-type diterpenoid. The analgesic activities of compounds 2–6, 8, and 10–15 were evaluated using an acetic acid-induced writhing test in mice. Compounds 3–6, 8, 10, 12, and 15 exhibited significant analgesic activity at 5 mg/kg (ip) compared to vehicle-injected mice (P

A novel asymmetric synthesis of a phenanthroindolizidine alkaloid, (+)-deoxytylophorinine, is reported, which uses a chiral nickel(II) complex of a glycine Schiff base to synthesize a substituted ( R )-3-phenanthrylalanine as a key intermediate and Meldrum’s acid to construct the E ring.

The NHC-catalyzed reactions of nitrosoarenes with 4-(2-aroylvinyl)furan-3-carbaldehydes, 4-(2-aroylvinyl)thiophene-3-carbaldehydes or 2-(2-aroylvinyl)nicotinaldehydes were studied, which produced novel furo[3,4-d][1,2]oxazin-4-ones, thieno[3,4-d][1,2]oxazin-4-ones or pyrido[3,2-d][1,2]oxazin-5-ones, respecti-vely. This work developed a versatile method for the construction of different types of heterocyclic ring-fused 1,2-oxazinones that are not easy accessible by other methods.

The photocycloaddition of five 9-substituted anthracenes [AnCH2N+(CH3)3Br- (1), AnCH2COO-Na+ (2), AnCH2OH (3), AnCOCH3 (4), and AnCH3 (5), An = 9-anthryl] incorporated within Nafion membranes has been investigated. While irradiation of the above compounds in homogeneous solutions, and 5 in Nafion also, mainly gave rise to their head-to-tail (h−t) photocyclomers, photoirradiation of the samples of 1−4 incorporated within Nafion membranes almost exclusively resulted in the head-to-head (h−h) photocyclomers. Furthermore, the h−h photocyclomers are significantly more stable in Nafion membranes than in homogeneous solutions. These observations can be explained in terms of the preorientation of the substrate molecules in the inverse micelle-like clusters of Nafion.

Supramolecular photochemistry is concerned with systems where non-covalent interactions become significant or dominate in determining the chemistry of guest/host systems. The supramolecular photochemistry of phenyl phenylacetates, photocycloaddition of diaryl compounds and the photooxidation of alkenes included in zeolites and Nafion membranes is the subject of this report.