The title compounds, 8-amino-6-methyl-3,4-diphenyl-1H-isochromen-1-one, C22H17NO2, (I), and 8-amino-3,4-diethyl-6-methyl-1H-isochromen-1-one, C14H17NO2, (II), are new isocoumarin derivatives in which the isochromene ring systems are planar. Compound II crystallizes with two independent mol­ecules (A and B) in the asymmetric unit. In I, the two phenyl rings are inclined to each other by 56.41 (7)° and to the mean plane of the 1H-isochromene ring system by 67.64 (6) and 44.92 (6)°. In both compounds, there is an intra­molecular N—H⋯O hydrogen bond present forming an S(6) ring motif. In the crystal of I, mol­ecules are linked by N—H⋯π inter­actions, forming chains along the b-axis direction. A C—H⋯π inter­action links the chains to form layers parallel to (100). The layers are then linked by a second C—H⋯π inter­action, forming a three-dimensional structure. In the crystal of II, the two independent mol­ecules (A and B) are linked by N—H⋯O hydrogen bonds, forming –A–B–A–B– chains along the [101] direction. The chains are linked into ribbons by C—H⋯π inter­actions involving inversion-related A mol­ecules. The latter are linked by offset π–π inter­actions [inter­centroid distances vary from 3.506 (1) to 3.870 (2) Å], forming a three-dimensional structure.

Alaska’s pristine coastline is ripe for an influx of invasive marine species such as the European green crab and the rough periwinkle (an Atlantic sea snail) warns a new study by a team of scientists from the Smithsonian Environmental Research Center.

The post Alaska’s cold waters no barrier to invasive marine species, scientists say appeared first on Smithsonian Insider.

A new study finds that since 1985, half of Australia's Great Barrier Reef coral has died.

The post Smithsonian marine biologist Nancy Knowlton discusses Great Barrier Reef coral dieoff on PBS NewsHour appeared first on Smithsonian Insider.

A rare Longman’s beaked whale found stranded on the Hawaiian island of Maui in 2010 has scientists in Hawaii on the alert for a deadly disease known as morbillivirus which can lead to high mortality rates in dolphins and other marine mammals.

The post Rare whale beached in Hawaii infected with deadly marine-mammal virus appeared first on Smithsonian Insider.

The goal of the project—the Smithsonian’s Tennenbaum Marine Observatories—is to monitor the ocean’s coastal ecosystems over a long period of time.

The post Smithsonian launches Global Marine Biodiversity Project with $10 million donation appeared first on Smithsonian Insider.

Emmett Duffy, currently the Gluckman Professor of Marine Science at the College of William & Mary in Virginia, has been appointed director of the Smithsonian’s […]

The post Emmett Duffy named director of Smithsonian’s Tennenbaum Marine Observatories Network appeared first on Smithsonian Insider.

(Study is one of dozens to be presented by bird scientists this week at the 2016 North American Ornithological Conference in Washington, D.C.) To catch tuna […]

The post Fishing gear entanglements of marine birds is focus of Smithsonian ecologist’s study appeared first on Smithsonian Insider.

An extraordinary arrangement of bristles, wrinkles and wart-like bumps cover the cold skin of Sphaerephesia amphorata, a new deep-sea worm described and named by researchers […]

The post Bizarre new marine worms covered in bristles, wrinkles & bumps appeared first on Smithsonian Insider.

Some of Hong Kong’s most disturbed and pristine marine environments were the recent focus of an intense 10-day MarineGEO survey of living organisms by a […]

The post MarineGEO survey conducted in Hong Kong appeared first on Smithsonian Insider.

Some of the earliest humans to inhabit America came from Europe according to a new book "Across Atlantic Ice: The Origin of America's Clovis Culture."

The post New book reveals Ice Age mariners from Europe were America’s first inhabitants appeared first on Smithsonian Insider.

A mysterious cycle of booms and busts in marine biodiversity over the past 500 million years could be tied to a periodic uplifting of the world's continents, scientists report

The post Boom and bust cycle of marine biodiversity every 60 million years linked to uplifting of continents appeared first on Smithsonian Insider.

The National Museum of Natural History will permanently display the Dom Pedro Aquamarine, which is the largest single piece of cut-gem aquamarine in the world, beginning Dec. 6.

The post Magnificent Dom Pedro aquamarine to go on view in the Smithsonian’s Natural History Museum appeared first on Smithsonian Insider.

In the battle against invasive species, giant commercial ships are on the front lines. But even when they follow the rules, one of their best […]

The post Battle against invasive marine species comes up short as global shipping surges appeared first on Smithsonian Insider.

Mark Torchin, a marine ecologist at the Smithsonian Tropical Research Institute (STRI) in Panama, talks about how he studies the parasites of invasive marine animals such as snails. Much of his research focuses on biological invasions and the dynamics between the host, the parasites and the surrounding ecosystem.

The post Meet our Scientist–Mark Torchin tracks invasive marine species and their parasites in Panama appeared first on Smithsonian Insider.

The post Belize’s South Water Caye Marine Reserve protects biodiversity of Belizean Barrier Reef appeared first on Smithsonian Insider.

“Our guide celebrates the beauty of some of the most attractive inhabitants of Panama’s undersea realm and provides an indispensable, easy-to-use tool for their identification,” say the Littlers.

The post Researchers compile colorful on-line guide to marine algae of Panama appeared first on Smithsonian Insider.

The Smithsonian Environmental Research Center has created NEMESIS--National Estuarine and Marine Exotic Species Information System--an online public database that provides key information about the non-native marine species throughout the United States.

The post New invasive species database allows public to ID marine invaders with a home computer appeared first on Smithsonian Insider.