Pulse compression over a 170-THz bandwidth in the visible by use of only chirped mirrors

We report on double-chirped mirrors with custom-tailored dispersion characteristics over a bandwidth of 170 THz in the visible. The mirrors are used in a prismless compressor for a noncollinear optical parametric amplifier in the visible. The compressed pulses, characterized for the what is believed to be first time by use of the spectral phase interferometry for direct electric field reconstruction technique, display a nearly flat phase from 510 to 710 nm and have a duration of 5.7 fs.     

The influence of stereochemistry on the mass spectra of some trimethylsilylated pyranoses

The relative intensities of certain ions in the mass spectra of trimethylsilylated pyranoses have been observed to depend on the stereochemistry of the molecule. A system has been developed which is capable of explaining the differences between the anomeric forms of D-glucose, D-galactose, D-mannose and D-xylose.     

Three new sesterterpenoid antibiotics from the marine sponge Luffariella variabilis (polejaff)

Structures of three new sesterterpenoid antibiotics 2, 3, and 4, isolated from a marine sponge have been determined by spectral analysis and chemical transformations.     

Manoalide,an antibiotic sesterterpenoid from the marine sponge luffariella variabilis (polejaeff)

The structure of manoalide ($\text{1}$), a new sesterterpenoid antibiotic isolated from a marine sponge, has been determined by spectral analysis and chemical transformations.     

Emblide,a new polyfunctional cembranolide from the soft coral sarcophyton glaucum

From a Pacific marine coelenterate we have isolated emblide, a cembrane diterpenoid which bears acetoxy, dienoic ester, and α,β-unsaturated ?-lactone functions. Its structure (1) was deduced from spectral and X-ray crystallographic data.     

The Kapakahines, Cyclic Peptides from the Marine Sponge Cribrochalina olemda

Four cyclic peptides, kapakahines A-D, were isolated from the marine sponge Cribrochalina olemda. Their structures including complete stereochemistry were elucidated by spectral analysis and chemical degradation. The unique structural feature of these peptides is the lack of an amide linkage between two tryptophan residues. Instead the ring is closed by a bond from the indole nitrogen of Trp-1 to the beta-carbon of Trp-2.     

Two new xenicin diterpenoids from the octocoral anthelia edmondsoni

From the soft coral Antheliaedmondsoni two new diterpenoids, waixenicin-A (1) and -B (2) have been Isolated. Their structures were elucidated by¹H and¹³C NMR analysis and the relative stereochemistry was determined by x-ray diffraction of crystalline waixenicin-B (2).