Oxytocin, synthetic

Impaired milk ejection may respond to nasal oxytocin. Synthetic peptide and nonpeptide oxytocin antagonists that can prevent premature labor are being investigated. 

Oxytocin, synthetic (Syntocinon, Pitocin) 1.007 0.17 0.017-0.10 IV infusion (1.0) Oxytocic (facilitates childbirth)... 

Table 2. Synthetic Analogues of Oxytocin with High Potency or Selectivity...

Table 4. Synthetic Analogues of Oxytocin and Vasopressin Having Antagonist Activities...

C Johansson, L Blomberg, W Hlebowicz, H Nicklasson, B Nilsson, L Andersson. Industrial production of an oxytocin antagonist Synthetic approaches to the development of a multi-kilogram scale solution synthesis. (Atosiban) In HLS Maia, ed. Peptides 1994. Proceedings of the 23rd European Peptide Symposium. Escom, Leiden, 1995, pp 34-35. 

Oxytocin is used for the induction of labor, or augmentation of labor in selected patients with uterine dysfunction, and to prevent or control bleeding after birth or abortion. Demoxytocin, a synthetic oxytocin has similar activities as oxytocin. 

Fig. 3A, B Neuropeptide effects on anxiety-related behavioiu. A The oxytocin receptor antagonist (black bars) administered intracerebroventricularly (i.c.v.) increased indices of anxiety-related behaviour in pregnant rats as measured on the elevated plus maze. Entries into the closed arms indicate unchanged locomotor activity. B Prolactin is an anxiolytic neuropeptide in female rats as revealed by i.c.v. administration of synthetic prolactin (grey and black bars represent two different doses) and by antisense targeting of the prolactin receptor (R). Vehicle (white bars) vs mixed bases (grey bars) and antisense oligodeoxynu-cleotide (black bars). p<0.05 vs vehicle (white bars). (Adapted from Nemnann et al. 2000) and Torner et al. 2001)...

The iodine oxidation method has also been applied in one-pot synthetic strategies to mono-disulfide peptides in which the bis-cysteine peptide is cleaved from the resin, depro-tected, and oxidized in a single step.163 64 A comparative analysis of the iodine procedure (TFA/10 equiv I2) with other TFA/oxidant mixtures using oxytocin as the target model peptide clearly revealed formation of side products to a significant extent. 85 ... 

The methods presented in the sections above are all suitable for the synthesis of lanthionines as amino acid derivatives. However, a very important synthetic goal remains the synthesis of lanthionine-containing peptides, for example the synthesis of lantibiotics and other peptide analogues where lanthionine has replaced cystine. In the following Sections some syntheses of lanthionine-containing peptides comprising analogues of cystine peptides, such as enkephalin, somatostatin, and oxytocin are described. 

A. General description Oxytocin is a nonapeptide (molecular weight 1.0 kDa) that differs by two amino acids from vasopressin it is stored and released from the posterior pituitary gland. Commercially available oxytocin is prepared synthetically. 

Oxytocin, desmopressin, cer-betocin and related synthetic peptides CEC Hypersil C8, CEC Hypersil Cl8, 5 pm, Spherisorb mixed mode C18/SCX phase 3 pm Triethylamine buffers, pH 3.0 adjusted with phosphoric acid with different proportion of acetonitrile 335 mm x 100 pm i.d. 250 mm packed length... 

Synthetic peptides such as oxytocin, vasopressin, ACTH, calcitonin, secretin, somatostatin, cyclosporine, and insulin are already in clinical use. 

Synthetic FI was treated using conditions known to convert oxytocin to a mixture of parallel and antiparallel dimers RPLC separation gave FI (20.1 min) and two more retained peaks at 42.0 and 45.3 min. The latter were analyzed by size-exclusion LC both had 1,570. 

Historically, the first important cysteine protecting group was the 5-benzyl group, developed by du Vigneaud etal. and used in the classical synthesis of oxytocin,t as well as in the syntheses of a number of cysteine-containing peptides in the first years of solid-phase synthetic methodology.P l This 5-Bzl protection is nowadays used infrequently due to the fact that its removal involves harsh conditions, e.g. sodium in liquid ammoniat or anhydrous hydrogen fluoride at 20°C,t conditions which may lead to side reactions such as elimination... 

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