Marine life as a source for breast cancer treatment: A comprehensive review.

Breast cancer, one of the most significant tumors among all cancer cells, still has deficiencies for effective treatment. Moreover, substitute treatments employing natural products as bioactive metabolites has been seriously considered. The source of bioactive metabolites are not only the most numerous but also represent the richest source. A unique source is from the oceans or marine species which demonstrated intriguing chemical and biological diversity which represents an astonishing reserve for discovering novel anticancer drugs. Notably, marine sponges produce the largest amount of diverse bioactive peptides, alkaloids, terpenoids, polyketides along with many secondary metabolites whose potential is mostly therapeutic. In this review, our main focus is on the marine derived secondary metabolites which demonstrated cytotoxic effects towards numerous breast cancer cells and have been isolated from the marine sources such as marine sponges, cyanobacteria, fungi, algae, tunicates, actinomycetes, ascidians, and other sources of marine organisms.

Phytochemical analysis and biological activities of "Cherchoomoro" (Nepeta adenophyta Hedge).

ETHNOPHARMACOLOGICAL RELEVANCE: Nepeta adenophyta Hedge (Lamiaceae) is an endemic therapeutic herb from Astore, Gilgit (Pakistan). This plant species has been reported among the local communities, especially for treating abdominal pain, kidney pain, menstrual pain, headache, and controlling bleeding disorders. Therefore, the scientific basis is provided for the relief of pain as it is used in various pain management among the natives, especially as ethnogynecological herbal remedy. AIM OF THE STUDY: The present study investigates the analgesic and anti-inflammatory effects of the ethanolic extract of N. adenophyta in animal models. Furthermore, the extract was also studied to determine their valuable phytoconstituents. MATERIAL AND METHODS: The biological effects were determined via tail-flick, hot plate, and acetic-acid-induced abdominal writhing methods. At the same time, anti-inflammatory activity was assesed via oxidative burst and antioxidant DPPH assay. Gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS) techniques were employed to understand the phytochemicals present in the crude ethanolic extract of Nepeta adenophyta. RESULTS: In the current study, Nepeta adenophyta extract exhibited potent analgesic and anti-inflammatory effects on different pain models and indicated that the analgesic effect of N. adenophyta extract is mediated both in central and peripheral ways. Dose-dependent and significant (P < 0.05) increases were shown in pain threshold, at 45 min post-treatment, with 20 and 40 mg/kg of the extract in the tail-flick model. The effects of the extract were similar to aspirin but lower to those by morphine (2.5 mg/kg) in the same tests. The extract (20-40 mg/kg) showed dose-dependent inhibition of writhing with a significant (P < 0.001) increase protection against thermal stimuli in hot plate test as compared to control and similar to aspirin and morphine. Further, the anti-inflammatory activity of the crude in oxidative burst and DPPH assays showed significant inhibitory activity. The chemical profile analysis showed major phytochemicals, including long chain derivatives of alkane and alcohol, phenolics, naphthalene, naphthopyran, androsten phenanthrenone, nepetalactones, flavonoids etc. CONCLUSIONS: Nepeta adenophyta Hedge is suggested as a natural alternative for mild pain relief. Our findings endorse the folklore use of N. adenophyta in different pain managements which can be attributed to the presence of polyphenolic compounds, naphthalene derivatives, flavanoids and nepetalactones etc.

A novel, chemoselective and efficient microwave-assisted deprotection of silyl ethers with selectfluor.

A novel microwave-assisted, chemoselective and efficient method for the cleavage of silyl ethers (aliphatic and aromatic) catalyzed by Selectfluor is reported. A wide range of TBS-, TIPS-, and TBDPS-protected alkyl silyl ethers can be chemoselectively cleaved in high yield in the presence of aryl silyl ethers. The chemoselective deprotection of phenolic TBS ethers, and not the TIPS- or TBDPS-protected phenolic ethers, and the deprotection of silyl esters were also achieved under these reaction conditions. In addition, the transetherification and etherification of benzylic hydroxy groups in alcoholic solvents is observed.

ZrCl4 as an efficient catalyst for a novel one-pot protection/deprotection synthetic methodology.

A catalytic quantity of ZrCl 4 (20 mol %) was found to be an efficient catalyst for the one-pot esterification and deprotection of (5 S,6 R)-5,6-diacetoxyoct-7-enoic acid in good yields (44-62%) with a lactone formed as a minor byproduct. ZrCl 4 (10-20 mol %) was also sufficient to deprotect 1,3-dioxalane, bis-TBDMS ethers, and diacetate functional groups in excellent yields of up to 93%. ZrCl 4 (1-10 mol %) also promoted diol protection as the acetonide in 90% yield and acted as a trans-esterification catalyst for a range of esters.

The chemoselective and efficient deprotection of silyl ethers using trimethylsilyl bromide.

An efficient and chemoselective cleavage of silyl ethers (primary, secondary and aromatic) by using catalytic quantities of trimethylsilyl bromide (TMSBr) in methanol is reported. A wide range of alkyl silyl ethers such as TBS, TIPS, and TBDPS can be chemoselectively cleaved in high yield in the presence of aryl silyl ethers. The deprotection of silyl esters was also achieved employing catalytic quantities of TMSBr.