We present an analysis of the Far Ultraviolet Spectroscopic Explorer (FUSE ) spectra of five V1093 Her (PG 1716+426) stars, the subgroup of hydrogen-rich subdwarf B stars that exhibit very low amplitude, long-period luminosity variations. Our primary aim is to investigate whether these stars display abundances which differ from those observed in the nonvariable sdB stars and also in the shorter period V361 Hya variables. For the light elements and for those beyond the iron peak, our abundances are consistent with the trends observed in earlier studies. For the important iron peak elements Ti, V, Cr, Mn, Fe, Co, and Ni, which are thought to be directly linked to the driving mechanism in both long-period and short-period variables, the abundances determined in the V1093 Her stars appear very homogeneous and exhibit mild enrichments (by factors of 2Y5 for Cr, Mn, Fe, and Co) over the solar value. However, these abundances do not differ appreciably from those measured in a sample consisting of constant stars and one short-period pulsator. The implications of these findings for current models which involve both diffusion processes and stellar winds to account for the driving of nonradial pulsations in sdB stars are discussed.

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Significance: The synthesis of novel macrocyclic peptides containing Pro-Gly sequences was achieved by exploiting oligomerization/cyclization/ cleavage sequential reactions on an oxime resin 1. Thus, the liner peptide sequence 5 (resin loading: 0.3 mmol/g) was prepared from 1 and Boc-Ala-OH via the standard solid-phase peptide synthetic method. The removal of the Boc group, followed by the oligomerization/cyclization/cleavage reaction with DIPEA in DMF, afforded cyclic peptides 6a-c in 51% (6a/6b/6c = 91:8:1). The methodology was applied to the three linear sequences of six to eight amino acids containing a Pro-Gly-Pro-Gly unit to give nine novel large macrocyclic peptides.Comment: Solvents (DMF or CH 2 Cl 2 ) and resin loading (0.3-1.2 mmol/g) in the oligomerization/ cyclization/cleavage reaction affected the yield and the ratio of the cyclic peptide oligomers. The cyclization of linear peptides is often quite difficult to achieve in high yield with all L-amino acid residues (