In this work, poly(lactic acid) (PLA) dimer model compounds with different tacticities were synthesized and studied in detail by 1H and 13C nuclear magnetic resonance (NMR) in three solvents, deuterated chloroform (CDCl3)/CCl4 (20/80 v/v), CDCl3 and dimethyl sulfoxide -d6. All of the peaks in the 1H and 13C NMR spectra were assigned with the help of two-dimensional NMR. Although the solvents we...

Chemical shifts of backbone atoms in proteins are exquisitely sensitive to local conformation, and homologous proteins show quite similar patterns of secondary chemical shifts. The inverse of this relation is used to search a database for triplets of adjacent residues with secondary chemical shifts and sequence similarity which provide the best match to the query triplet of interest. The databa...

Assignment of the fifteen carbons of terrecyclic acid A, C15H20O3, a new sesquiterpene antibiotic, in the 13C NMR spectrum was performed by 13C-[1H] selective proton decoupling experiments, comparison with spectra of its derivatives and chemical shifts.

Calculations suggest that some carbon chemical shifts in proteins should have large ring current shifts (> 1 ppm). We present 13C, 15N and 1H assignments for cytochrome C2 from Rhodospirillum rubrum, compare these with shifts for other cytochromes c, and show that the calculated ring current shifts are similar to experimentally observed shifts, but that there remain substantial conformation-dep...

During the past three years it has become possible to compute ab initio the 13C, 15N and 19F NMR chemical shifts of many sites in native proteins. Chemical shifts are beginning to become a useful supplement to more established methods of solution structure determination, and may find utility in solid-state analysis as well. From 13C NMR, information on phi, psi and chi torsions can be obtained,...

Proton-detected 1H-13C heteronuclear correlated spectroscopy [( 1H,13C]-COSY) was used to establish relations between the carbon-13 and proton nuclear magnetic resonance chemical shifts in the hexadeoxynucleoside pentaphosphate d-(GCATGC)2. Using the previously established sequence-specific proton NMR assignments, sequence-specific assignments were thus obtained for nearly all proton-bearing ca...