THE THYMOLYTIC ACTIVITY OF 6- AND 9-HALOCORTICOIDS AND RELATED STEROIDS

1965 ◽  
Vol 49 (2) ◽  
pp. 262-270 ◽  
Author(s):  
Ralph I. Dorfman ◽  
P. G. Holton ◽  
Fred A. Kind
Keyword(s):  
Double Bond ◽  
Subcutaneous Injection ◽  
Fluocinolone Acetonide ◽  
Relative Potency ◽  
Subcutaneous Route ◽  
Adrenalectomized Rats

ABSTRACT Adrenalectomized rats were used for the determination of the relative potency of various 6- and 9-halo substituted corticoids administered subcutaneously or by gavage using thymus weightas the endpoint. By subcutaneous injection, fluocinolone acetonide was the most active corticoid at 700 times that of cortisol. This compound was also the most active corticoid by the gavage route and was judged to be 570 times as active as the standard cortisol. The introduction of the 16,17-acetonide and 16,17-acetone 21-acetate groups into 17α,21-dihydroxy-9α,11β-dichloropregna-1,4-diene-3,20-dione increased the activity by a factor of 42 and 100, respectively. The introduction of the δ1 double bond into 6α-fluoroprogesterone 16,17-acetonide caused an increase of 10-fold in thymolytic activity assessed by the subcutaneous route

ANTI-OVULATORY ACTIVITY OF STEROIDS ADMINISTERED BY GAVAGE IN THE ADULT OESTRUS RABBIT

1963 ◽  
Vol 42 (2_Suppl) ◽  
pp. S17-S30
Author(s):  
Fred A. Kind ◽  
Ralph I. Dorfman
Keyword(s):  
Dose Response ◽  
Active Compound ◽  
Subcutaneous Injection ◽  
Response Curve ◽  
Parent Compound ◽  
Dose Response Curve ◽  
Relative Potency ◽  
Reference Standard ◽  
Highly Active ◽  
Dose Levels

ABSTRACT Thirty-seven steroids have been studied as orally effective inhibitors of ovulation in the mated oestrus rabbit. Norethisterone served as the reference standard and a dose response curve was established between the 0.31 and 1.25 mg dose levels. Nine highly active anti-ovulatory compounds are described listed in a decreasing order of potency with norethisterone having the arbitrary value of one: 6-chloro-Δ6-dehydro-17α-acetoxyprogesterone (35), 6α-methyl-Δ1-dehydro-17α-acetoxyprogesterone (≥ 10), 6-fluoro-Δ6-dehydro-17α-acetoxyprogesterone(9), 6-methyl-Δ6-dehydro-17α-acetoxyprogesterone (5), Δ6-dehydro-17α-acetoxyprogesterone (≥ 3), 6α-methyl-17α-acetoxyprogesterone (2.6), 6-chloro-Δ1,6-bisdehydro-17α-acetoxyprogesterone (≥ 2), 2-hydroxymethyl-17α-methyl-17β-hydroxyandrostan-3-one (≥ 2), and 6α-fluoro-16α-methyl-17α-acetoxyprogesterone (≥ 1.25). The anti-ovulatory activity of a compound was not related necessarily to the progestational activity of a compound nor to the anti-gonadotrophic activity as measured in parabiotic rats. 6-Chloro-Δ60dehydro-17-acetoxyprogesterone was as effective by gavage as previously shown by subcutaneous injection. 2-Hydroxymethyl-17α-methyl-17β-hydroxyandrostan-3-one was at least 2.5 times more active by gavage than by injection. While 17α-acetoxyprogesterone was a very weak anti-ovulatory steroid, modifications of the structure by addition of methyl or halogen at the 6α position with or without unsaturation greatly increased the activity. 6-Chloro-Δ6-dehydro-27α-acetoxyprogesterone was the most active compound in this series showing a relative potency of 3500 times that of the parent compound 17α-acetoxyprogesterone.

Gradient-Enhanced Inverse-Detected NMR Techniquesfor Determination of 1H-15N Coupling Constants in 2,2-Dimethylpenta-3,4-dienal Derivatives

1997 ◽  
Vol 62 (11) ◽  
pp. 1747-1753 ◽  
Author(s):  
Radek Marek
Keyword(s):  
Double Bond ◽  
Chemical Shifts ◽  
Multiple Bond ◽  
Coupling Constants ◽  
Single Quantum ◽  
Nmr Techniques ◽  
Phase Sensitive ◽  
Heteronuclear Coupling

Determination of 15N chemical shifts and heteronuclear coupling constants of substituted 2,2-dimethylpenta-3,4-dienal hydrazones is presented. The chemical shifts were determined by gradient-enhanced inverse-detected NMR techniques and 1H-15N coupling constants were extracted from phase-sensitive gradient-enhanced single-quantum multiple bond correlation experiments. Stereospecific behaviour of the coupling constants 2J(1H,15N) and 1J(1H,13C) has been used to determine the configuration on a C=N double bond. The above-mentioned compounds exist predominantly as E isomers in deuteriochloroform.

Effects of Niacin and Vitamin C on Blood Sugar

1958 ◽  
Vol 192 (3) ◽  
pp. 511-513 ◽  
Author(s):  
G. N. Bera ◽  
J. Chowdhury
Keyword(s):  
Vitamin C ◽  
Blood Sugar ◽  
Blood Level ◽  
Subcutaneous Injection ◽  
Intramuscular Injection ◽  
Liver Glycogen ◽  
Simultaneous Administration ◽  
Diabetic Rabbits ◽  
Adrenalectomized Rats

Intramuscular injection of niacin in normal rats induces hyperglycemia which lasts approximately 1 hour. In adrenalectomized rats niacin produces a hypoglycemia. Subcutaneous injection of vitamin C lowers blood sugar in normal and diabetic rabbits, the effect being pronounced when the blood level of vitamin C is high. The simultaneous administration of niacin and vitamin C produced a pronounced hypoglycemia. The rise in blood sugar normally produced by niacin is nullified if vitamin C is injected simultaneously or shortly thereafter. In both normal and diabetic animals, vitamin C injections produce an increase in liver glycogen. The vitamin C content of liver is lower in normal than in alloxan diabetic animals.

Two Validated Chromatographic Methods for Determination of Ciprofloxacin HCl, One of its Specified Impurities and Fluocinolone Acetonide in Newly Approved Otic Solution

2021 ◽  
Author(s):  
Mahmoud A Tantawy ◽  
Israa A Wahba ◽  
Samah S Saad ◽  
Nesrin K Ramadan
Keyword(s):  
High Performance ◽  
Fluocinolone Acetonide ◽  
Ultraviolet Detection ◽  
Chromatographic Methods ◽  
Bulk Powder ◽  
Developing System ◽  
Layer Chromatography ◽  
Chloroform Methanol ◽  
Linear Regressions

Abstract Two sensitive, selective and precise chromatographic methods have been established for concomitant quantification of ciprofloxacin HCl (CIP), fluocinolone acetonide (FLU) along with ciprofloxacin impurity A (CIP-imp A). The first method was thin-layer chromatography (TLC-densitometry) where separation was accomplished using TLC silica plates 60 G.F254 as a stationary phase and chloroform–methanol–33%ammonia (4.6:4.4:1, by volume) as a developing system. The obtained plates were scanned at 260 nm over concentration ranges of 1.0–40.0, 0.6–20.0 and 1.0–40.0 μg band−1 for CIP, FLU and CIP-imp A, respectively. The second method was based on high-performance liquid chromatography using a Zorbax ODS column (5 μm, 150 × 4.6 mm i.d.) where adequate separation was achieved through a mobile phase composed of phosphate buffer pH 3.6–acetonitrile (45:55, v/v) at flow rate 1.0 mL min−1 with ultraviolet detection at 254 nm. Linear regressions were obtained in the range of 1.0–40.0 μg mL−1 for CIP, 0.6–20.0 μg mL−1 for FLU and 1.0–40.0 μg mL−1 for CIP-imp A. The suggested methods were validated in compliance with the International Conference on Harmonization guidelines and were successfully applied for determination of CIP and FLU in bulk powder and newly marketed otic solution.

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