Dr. Alfredo Santos is known for his studies in the chemistry of natural harvest. He has completed a lot of work in the segregation and elucidation of the phaeantharine and other alkaloids from Philippine medical plants. He was elected as Academician in 1978 and conferred as National Scientist in 1978.
Dr. Santos served in different capacities at the University of the Philippines for 45 years until he stop working in 1965 as Dean of the College of Pharmacy. After his UP stint, Dr. Santos sustained to do study at the UST Research Center and the National Institute of Science and Technology (NAST).
In appreciation of his innovative experimental researches in various alkaloids isolated from Philippine medicinal plants, he acknowledged Pres. Magsaysay's Distinguished Service Star in 1954. In 1953, he is also a receiver of the Outstanding Pharmacist Researcher of the Philippine Pharmaceutical Association and Phil AAS Outstanding Scientist Award in 1973.