"I like to understand the things around us at the molecular level," he says. "I liked physics but it is hard to relate it to the world around you."

Schreiber did his graduate work and obtained his Ph.D. in chemistry from Harvard in 1981. The same year, he went directly to a Yale assistant professorship, bypassing the usual postdoctoral fellowships or waffling.

And the wooing of the already hot young professor began almost immediately.

"I began to receive job offers after a few years and I almost moved," he says.

But in 1988 he finally took a professorship at Harvard, where he is now familiar to undergrads as the teacher of introductory orgo classes Chemistry 17 and Chemistry 27.

Schreiber's research today focuses on cell biology, which he calls "one of the most explosive areas in research."

His work has developed new links between chemistry and biology. He is a pioneer in the burgeoning field of chemical biology.

"Stuart's greatest contribution to Harvard thus far is the same as his greatest contribution to science," says Cabot Associate Professor of Chemistry Gregory L. Verdine. "By essentially creating a new field of research, chemical cell biology, he has brought a great deal of attention to Harvard as a place where extremely innovative science is done at the interface of chemistry and biology."

Schreiber's research into signal transduction, whose malfunction is the first step in cancer has practical applications as well.

"We studied signal transduction," Schreiber says,. "This involved looking at natural products that had effects on cells that caused them to no longer proliferate."

One of those products, cyclosporin, had potential as a lifesaving drug, he says.

His work led to the creation of a new pharmaceutical company in Cambridge, Ariad Pharmaceuticals, which has continued work on the possible applications of cyclosporin.

Schreiber says his own research is not focusing on the substance or its applications, however.

His work on cell biology consumes all his time, he says leaving few hours for anything but commuting in the Porsche and a rare hobby or two.

Occasionally, he says, he jogs, walks with his wife or watches movies.

But as befits the hottest young chemist around, most hours are spent in the lab.

"I'm here seven days a week, 365 days a year," he says.