Synthesis of primary aromatic amides by aminocarbonylation of aryl halides using formamide as an ammonia synthon.

Primary aromatic amides were prepared by a palladium-catalyzed aminocarbonylation reaction of aryl halides in high yields (70-90%) using formamide as the amine source. The reactions require a palladium catalyst in combination with a nucleophilic Lewis base such as imidazole or 4-(dimethylamino)pyridine (DMAP). Aryl, heteroaryl, and vinyl bromides and chlorides were converted to the primary amides under mild conditions (5 bar, 120 degrees C) using 1 mol % of a palladium-phosphine complex. Best results were obtained in dioxane using triphenylphosphine as the ligand and DMAP as the base. For activated aryl bromides, a phosphine-to-palladium ratio of 2:1 was sufficient, but less reactive aryl bromides or aryl chlorides required ligand-to-palladium ratios up to 8:1 in order to stabilize the catalyst and achieve full conversion. The influence of catalyst, base, solvent, pressure, and temperature was studied in detail. The mechanism of the reaction could be clarified by isolating and identifying the reaction intermediates. In addition, methylamides and dimethylamides were prepared by the same method using N-methylformamide and N,N-dimethylformamide as the amine source.

Atom-Efficient Oxidation of Alkenes with Molecular Oxygen: Synthesis of Diols.

Dihydroxylations of simple alkenes were carried out for the first time in excellent yields and selectivities with molecular oxygen as oxidant [(Eq. (a)]. Both oxygen atoms are used productively and are incorporated into the product in this transition metal catalyzed alkene oxidation.

The decrease in growth hormone (GH) response after repeated stimulation with GH-releasing hormone is partly caused by an elevation of somatostatin tonus.

Repeated injection of GHRH leads to a decrease in the GH response in normal subjects. Arginine (Arg) stimulates GH secretion by suppression of hypothalamic somatostatin. To confirm these findings, eight normal men were examined in a series of five settings: test 1 (GHRH/GHRH-TRH), 100 micrograms GHRH injected iv, followed by 100 micrograms GHRH, iv, after 120 min and 200 micrograms TRH, iv, after 150 min; test 2 (GHRH/Arg-TRH), like test 1, but instead of the second GHRH injection, a 30 g Arg infusion over 30 min; test 3 (GHRH/GHRH-Arg-TRH), like test 1, but additionally a 30 g Arg infusion after 120 min; test 4 (GHRH-Arg-TRH), iv GHRH and Arg infusion initially, followed by iv TRH after 30 min; and test 5 (TRH), 200 micrograms TRH, iv, at 0 min. For statistical evaluation, the area under the GH curve (AUC) from 0-120 min was compared with the AUC from 120-240 min. The GH response to the second administration of GHRH was significantly lower (P < 0.02) than the first increase [AUC, 0.5 +/- 0.01 min.mg/L (mean +/- SE) vs. 1.2 +/- 0.3]. No significant differences were found between the GH responses to either GHRH or Arg alone (AUC, 0.9 +/- 0.2 min.mg/L vs. 0.9 +/- 0.2). A larger GH increase (P < 0.02) was seen after GHRH-Arg compared to GHRH alone (AUC, 1.9 +/- 0.4 min.mg/L vs. 1.2 +/- 0.3). The GH response (P < 0.02) to GHRH-Arg stimulation was lower after previous GHRH injection than after GHRH-Arg stimulation alone (AUC, 1.9 +/- 0.4 min.mg/L vs. 3.5 +/- 0.9). There was a statistically significant difference between the TRH-stimulated TSH response in test 4 compared to that in test 5. We could show that decreasing GH responses to repeated GHRH can be avoided by a combined stimulation with GHRH/Arg. These findings suggest that the decreased GH response to a second GHRH bolus may be partly due to an elevated hypothalamic somatostatin secretion, which can be suppressed by Arg. The lower GH response to GHRH-Arg stimulation after a previous GHRH bolus suggests, furthermore, that the readily available GH pool in the human pituitary may be limited.

Changes in anterior pituitary response in patients with idiopathic hypothalamic hypogonadism caused by pulsatile GnRH therapy and testosterone replacement.

OBJECTIVE: This study evaluated in male patients with idiopathic hypothalamic hypogonadism the effect of pulsatile GnRH therapy or testosterone replacement on the response of all anterior pituitary hormones to adequate dynamic stimuli. PATIENTS AND DESIGN: In nine patients with idiopathic hypothalamic hypogonadism--mean age 21 +/- 1 (mean +/- SE)--a combined pituitary stimulation (CPS) with 200 micrograms TRH, 100 micrograms GnRH, 100 micrograms CRH and 100 micrograms GRH and an insulin tolerance-test (ITT) with 0.1 U insulin/kg body weight were performed. Both tests were repeated during pulsatile GnRH therapy and thereafter on testosterone replacement. MEASUREMENTS: Hormone levels were measured by immunometric assays. For statistical analysis the area under the curve (AUC) was used as a measure for hormone response. RESULTS: Testosterone levels did not differ significantly during GnRH therapy (16.6 +/- 2.1 nmol/L) and testosterone replacement (18.5 +/- 1.7 nmol/L). No significant differences were observed before and during the two treatment modalities for TSH and ACTH. PRL increase was significantly higher during GnRH therapy (AUC: 73580 +/- 8940) compared to the rise before treatment (AUC: 36161 +/- 5853; p < 0.01) and on testosterone replacement (AUC: 49995 +/- 6158; p < 0.01). The GH response to CPS and ITT was higher under testosterone replacement (AUC: 1826 +/- 353 and 1423 +/- 125) compared with the pretreatment situation (AUC: 727 +/- 115; p < 0.05 and 541 +/- 110; p < 0.01) and also more pronounced than under GnRH therapy (AUC: 1148 +/- 180 and 798 +/- 129; p < 0.05). FSH and LH after CPS rose significantly more during GnRH therapy (AUC: 864 +/- 122 and 2215 +/- 219) than before (AUC: 418 +/- 61 and 1424 +/- 277; p < 0.01) and on testosterone treatment (342 +/- 83 and 1153 +/- 323; p < 0.05). CONCLUSION: These results show that GnRH exerts a stimulatory effect on PRL secretion and may modulate GH secretion independently from sex steroids.

Immunoreactive inhibin in human follicular fluid in an ovarian hyperstimulation programme for in vitro fertilization: correlations and different forms.

UNLABELLED: The inhibin concentration in 131 samples of human follicular fluid obtained from 31 women undergoing ovarian hyperstimulation for in vitro fertilization was measured using specific double antibody radioimmunoassay. We used the synthetic 1-32-alpha-inhibin as standard and radioiodinated 1-32-Tyr-alpha-inhibin as tracer. Antibodies were raised in rabbits by immunization with the synthetic peptide. Estradiol and progesterone concentrations were measured using commercial radioimmunoassays. RESULTS: The inhibin concentration correlated with the estradiol (r = 0.57, N = 88, p < 0.0001) and progesterone (r = 0.82, N = 88, p < 0.0001) concentrations in human follicular fluid. The dosage of human menopausal gonadotropin given to individual patients correlated with the average inhibin concentration measured in their follicles (r = 0.72, N = 23, p < 0.0001). Similarly, the size of follicles correlated with their inhibin content (r = 0.75, N = 131, p < 0.0001). Nineteen samples of human follicular fluid originating from follicles of different size and volume were examined using gel-chromatography. In each human follicular fluid the main form of inhibin (32 kDa) was recovered. In small follicles (3 ml) we found 12.8 +/- 9.1% (mean +/- SD) of the whole immunoreactive inhibin eluting in the area of Vo (> or = 80 kDa). In the larger follicles (4-7 ml), however, only 4.4 +/- 4.2% of this large inhibin form could be found. CONCLUSIONS: Our data confirm that human menopausal gonadotropin stimulates ovarian inhibin production. In addition to the estradiol and progesterone concentrations, the inhibin concentration may be an index of granulosa cell function and follicular maturation. The occurrence of large molecular weight forms of inhibin in small follicles remains unclear. They may represent large precursor molecules which are proteolytically cleaved in more mature follicles.

[The rectus abdominis syndrome]. / Rectus-abdominis-Syndrom.

Three athletes (one female, two males), aged 18-21 years, developed acute abdominal pain, two of them immediately after exercise including abdominal muscle training. The female patient had a pulmonary infection of uncertain cause at the time. The second patient obviously suffered from an allergic or parasitic disease (eosinophilia of 26%). The third patient, a swimmer, had the symptoms in the course of a flu-like infection after drinking about 100 g alcohol. Serum creatinine kinase activity was 7,800-17,500 U/l, making acute muscle damage likely, probably rhabdomyolysis. Ultrasound examination revealed echo-dense areas of the rectus abdominis muscle in two of the patients, in one of them associated with marked muscle swelling. In the third patient ultrasound was unremarkable during a symptom-free interval 8 days after the onset of symptoms. These observations indicate that even during banal infections sport exercise involving special strain on the abdominal musculature should not be undertaken because of the risk of rhabdomyolysis.

Comparison of gonadotropin-releasing hormone and gonadotropin therapy in male patients with idiopathic hypothalamic hypogonadism.

OBJECTIVE: To compare pulsatile gonadotropin-releasing hormone (GnRH) therapy with gonadotropin therapy in male patients with idiopathic hypothalamic hypogonadism. DESIGN: Prospective study. Patients had free choice between the two forms of therapy. SETTING: Patients were treated on an outpatient basis in our department. PATIENTS: Eighteen patients of matched age (mean [+/- SD] age: 21.1 +/- 3.0 years and 23.6 +/- 7.3 years) and similar testicular volume were treated in each group. INTERVENTIONS: Pulsatile GnRH therapy was started with 4 micrograms GnRH subcutaneously every 2 hours using a portable pump and gonadotropin therapy with 3 x 2,500 IU human chorionic gonadotropin (hCG) weekly injected intramuscularly. After 8 to 12 weeks of hCG treatment, 150 IU human menopausal gonadotropin two to four times weekly were added. RESULTS: Testosterone (T) and estradiol (E2) levels increased significantly higher (T: P less than 0.03; E2; P less than 0.001) in the gonadotropin group than in the GnRH group (T: 22.5 +/- 8.1 versus 16.8 +/- 5.5 nmol/L; E2: 150 +/- 70 versus 88. +/- 59 pmol/L). Five patients developed gynecomastia during gonadotropin therapy. The rise of testicular volume was significantly more pronounced (P less than 0.001) in the GnRH group (delta testicular volume = 8.1 +/- 2.0 mL) than in the gonadotropin group (delta testicular volume = 4.8 +/- 1.8 mL). Ten patients of the GnRH and 8 of the gonadotropin group had positive sperm counts, ranging from 1.5 to 26 x 10(6) spermatozoa/mL. The latter was achieved more rapidly in the GnRH group (12 +/- 1.6 versus 20 +/- 2.3 months: P less than 0.02). CONCLUSIONS: Endocrine and exocrine testicular function can be normalized by both forms of therapy. Gonadotropin therapy has more side effects. Gonadotropin-releasing hormone leads to a higher testicular volume and a more rapid initiation of spermatogenesis compared with gonadotropin therapy.

Long-term treatment with SMS 201-995 in resistant acromegaly: effectiveness of high doses and continuous subcutaneous infusion.

Seventeen patients (8 women and 9 men) resistant to all other forms of therapy were treated with the somatostatin analogue SMS 201-995 (octreotide, Sandostatin). The duration of treatment ranged from 1 to 5 years. Mean GH levels of only 4 patients were suppressed under 5 micrograms/L during an 8 h serum profile with the standard dose of 0.1 mg 2 or 3 times daily. This standard dose suppressed mean GH levels in 10 other patients more than 50% of baseline, but for optimal effect higher doses up to 1.5 mg, 4 daily injections or continuous subcutaneous infusion (CSI) were needed. Octreotide had no influence on GH secretion in 3 patients. Suppression of mean GH levels under 5 micrograms/L was achieved in 10 patients. Normalization of insulin-like growth factor I (IGF-I) occurred in only 5 patients. Altogether, therapy with SMS 201-995 reduced GH levels from 23.8 +/- 32.2 micrograms/L (mean +/- SD) to 6.7 +/- 5.0 micrograms/L by 71.8% and IGF-I levels from 7.9 +/- 3.1 U/ml to 3.2 +/- 1.6 U/ml by 59.5%. We conclude that 1) treatment with SMS 201-995 in patients resistant to other forms of therapy may be less successful than previously reported for heterogenous groups of patients; 2) the dose regimen must be adapted to the individual patient for optimal effect and most of our patients needed higher doses than 300 micrograms daily; 3) 4 or maybe more daily injections or CSI seem to be most effective; and 4) in a minority of patients SMS has no influence on GH-secretion.

Interaction of L-dopa and GHRH on GH secretion in normal men.

To determine how L-dopa stimulates GH secretion, we investigated its interaction with GHRH in vivo. Six normal men were studied on 4 occasions: 1) L-dopa-TRH: 500 mg L-dopa orally followed by 200 micrograms TRH 60 min later; 2) L-dopa-GHRH-TRH: 100 micrograms GHRH 1-44 iv 30 min after L-dopa followed by 200 micrograms TRH iv; 3) GHRH-TRH: 100 micrograms GHRH iv at 0 min, 30 min later 200 micrograms TRH iv; 4) TRH test: 200 micrograms TRH iv as a bolus. After L-dopa-TRH GH-levels increased significantly from 0.6 micrograms/l to 25.8 +/- 9.6 (SE) micrograms/l at 60 min. Only a slight TSH and no PRL increase was observed after L-dopa-TRH. After L-dopa-GHRH-TRH the GH-increase was significantly higher (45.7 +/- 11.1 micrograms/l) compared to L-dopa-TRH alone. GHRH-TRH increased GH-levels to 52.5 +/- 12.1 micrograms/l, which was not significantly different from the GH-levels obtained when L-dopa-GHRH-TRH were given. TRH increased serum TSH and PRL to 6.3 +/- 0.7 microU/ml and 715 +/- 136 microU/ml, respectively, which was significantly higher compared to the TSH responses after L-dopa-TRH. The PRL and TSH increase after TRH only was also higher (TSH-max: 5.7 +/- 0.5 microU/ml; PRL-max: 899 +/- 154 microU/ml) compared to the TSH and PRL responses after L-dopa-TRH. Our results show that the combination of L-dopa with GHRH leads to the same GH response as GHRH only. However, both responses are significantly higher than the one after L-dopa alone.(ABSTRACT TRUNCATED AT 250 WORDS)